Just at that time, the Chinese and Vietnamese army and people were dealing at the French invaders one heavy blow after another in Vietnam. Therefore, besides such activities of conspiracy as some Frenchmen's soliciting roving bandits at Macao, it was said that some Frenchmen were plotting to buy or lease Macao from the Portuguese to anchor warships and station troops, using Macao as a springboard to attack Canton. Upon hearing the news, the Qing government directed Zhang Zhidong, the Viceroy of the Two Guangs, to quickly strengthen defence near Macao. Zhang presented notes to the Portuguese authorities in Macao over and over again, demanding that the Portuguese authorities abide by international law, and not provide the French with materials like food, fresh water, ammunition and others, and nor let the French recruit soldiers in Macao, "so as to promote friendship".

In early 1885, after the French suffered many defeats, the Portuguese cortes discussed French proposal to exchange Macao and Guinea, occupied by the Portuguese, for Congo, occupied by the French. Due to the eloquent protests of the representatives of Macao, the motion was aborted. Nevertheless, in that year, the Portuguese consul to Shanghai openly claimed that since Portugal and China had not exchanged peaceful treaty, there was no need for Portugal to observe neutrality. The statement sounded as if the Portuguese was going to let the French use Macao, which forced the Qing government to instruct the officials in Shanghai to "win over and restrain the Portuguese consul through tactful persuasion".

The British were also worried. They feared that if Portugal should transfer Macao to France, a French colony posing a threat to Hong Kong would appear in the area. Moreover, Macao was at the delta of the Pearl River and the Xijiang River, and since the end of the Sino-French War, the French had been contending for the commercial interests along the Xijiang River with the British. Therefore, the British intended either to help the Portuguese to conclude a treaty confirming its occupation of Macao with China, or to instigate China to "buy back" Macao or let the British themselves buy Macao. In any case, the British would never tolerate Macao's falling into the hands of another big Western power. The opportunity the Portuguese had awaited for many years had now come.

In July 1885, China and Britain concluded "Additional Articles to the Agreement of Chefoo", which stipulated that the opium shipped to China by the British could be marketed and shipped around freely after paying off the customs tariff and commercial tax with lump-sum payment. In the summer of 1886, in order to implement this new regulation, the Qing government sent Shao Youlian, an important customs official, and the British Robert Hart, the Inspector General of Chinese Customs, to Hong Kong to discuss implementation with the British Governor of Hong Kong. The British put forward eight requests, including that the tariff and inland commercial tax of opium should be levied together in both Macao and Hong Kong. Their purpose was to avoid the British suffering losses in case the new regulation was carried out in Hong Kong alone, and to end the unfavourable condition to Hong Kong that the Chinese customs levied the taxes of Chinese ships and goods going into and out of Hong Kong according to regulations concerning foreign ships and goods, while levying the taxes of those going into and out of Macao according to domestic tax rate. They also hoped to force the Qing government to hold formal talks with the Portuguese, so as to confirm the Portuguese occupation of Macao.

It was natural for Robert Hart to serve the British Empire. In addition, Hart was promoting his private interests by expanding the power of the Inspector General of Customs from maritime customs to inland customs through levying the customs tariff and inland commercial tax of opium together. That was why Hart vigorously promoted the public opinion among the top Chinese officials that China should conclude a treaty with Portugal, claiming that it would be very difficult to "buy Macao back even with a huge sum of money", and that it was quite possible that the Portuguese might hand Macao over to France, German, Russia or another country. He also advocated leasing Macao to Portugal without rents, and said that would bring no harm to the state system of China; instead, the tariff and tax of opium could be successfully levied. This demagoguery hit home those like Li Hongzhang and others often advocating appeasement towards Westerners. And because of Hart's "fairly good reputation" in his dealing with Westerners on behalf of China in the past, the Qing government sent him to Macao to talk with the Portuguese as he saw fit. Before the negotiation between China and Portugal was started, the Qing government had already fallen into the British trap.

Starting on July 21, Hart shuttled to and fro between Hong Kong and Macao three times to talk with the Governor of Macao, Thomas de Roza, who was about to leave his post for home, about Macao's co-operation in collecting the tariff and tax of opium together. Roza was overjoyed, and took the opportunity to request Portugal's perpetual occupation and government of Macao and half of the Inner Harbour. He also asked that China lease or cede three islands, Duimianshan (Lapa), Damaliuzhou and Xiaomaliuzhou, to Portugal and close down of the Chinese customs stations near Macao. The officials of the Foreign Office of the Qing government originally had only prepared to agree to let the Portuguese "live in Macao and use the place". Now suddenly they were informed that the Portuguese were requesting the closing of customs stations and attempting to occupy Duimianshan and half of the Inner Habour. They telegraphed Hart in haste, pointing out that the Portuguese Governor of Macao added these two terms, both of which harmed China's interests and could never be approved. They asked Hart to give the matter further consideration and discuss it later; if the Portuguese should stick to their guns, the only way was to stop negotiation for the time being.

Hart, however, would not give up. Defying the objection from the Chinese Foreign Office, he agreed to Roza's terms privately without authorization and signed a "Protocol" and "The Renewed Articles about Opium" with Roza. The protocol had ten articles. The four most important were:

First, China agreed to Portugal's perpetual occupation and government of Macao and its dependencies.

Second, Portugal would co-operate with China in levying opium tariff and tax in accordance with "The Renewed Articles about Opium".

Third, China would withdraw its patrolling boats and close down the customs stations near Macao.

Fourth, when carrying out the task stipulated in the "Renewed Articles about Opium", the Portuguese could stay on the three islands specified above.

In order to deceive the top officials in the Foreign Office, in his report to them, Hart pretended that the protocol and the articles were Roza's unilateral proposals. He cooked up some "reasons" to lure the officials into accepting this agreement, arguing that the words of "Portugal's occupation and government of Macao" only recognized the status quo that had existed for many years. Portugal could not possibly do more than what they did in the past on the basis of such wording. The closing down of the customs stations would reduce the tax revenue of the Guangdong government, but "if the customs stations are not closed down, the state can not have the revenue combining tariff and tax of opium together. Why save a little only to lose a lot?" Duimianshan was useless to China, and leasing it to Portugal with conditions would make the Portuguese carry out the special articles concerning opium revenue. All these words showed that for the sake of the interests of the British Empire and himself, Hart would not hesitate for a moment to damage China's sovereignty.

Due to the extreme difficulties in finance, after the discussion of the ministers, the Qing government agreed to use the "Macao status clause" in exchange for Portugal's co-operation in opium revenue work. The Foreign Office also agreed to send Hart's trusted follower, James Duncan Campbell, as his representative to Lisbon to negotiate with Portuguese government. The ministers, however, resolutely rejected the withdrawal of the customs stations outside Macao, and refused to cede or lease Duimianshan to Portugal. The newly appointed Grand Minister of the Foreign Office, Zeng Jize, spared no efforts in opposing the clause about Macao's status. He advocated for a complete avoidance of the Macao problem in the Sino-Portugal treaty. At most he was willing to accept such wording as that China agreed to lease Macao perpetually to Portugal with no rent or that China agreed to let the Portuguese govern Macao as before while Portugal paying China 500 taels of silver in rent per year. These directives from the Foreign Office forced Campbell to hold lengthy talks with his counterpart, the Portuguese Foreign Minister, Henrique de Barros Gomes, beginning in November, 1886. While the talks were proceeding Barros Gomes and other Portuguese officials were trying to occupy even more of the territory around Macao. Gomes brazenly said that Portugal had controlled Duimianshan for three centuries and demanded that Portugal be allowed to occupy the island. Gomes' activities endangered the treaty between China and Portugal, much to the distress of Hart, who was controlling the negotiations behind the scenes. Through Campbell, Hart repeatedly warned Gomes that if the Portuguese should miss this good opportunity, it would never come again, and it would be out of the question for Portugal to sign any treaty with China in the future. China would never recognize Portugal's status in Macao. Hart also made back-up plans in case the negotiations should break down, directing Campbell, if all else failed, to try to buy back Macao for China.

The Portuguese did not want to let such a golden opportunity slip away either. After complicated negotiations, they withdrew the demand for Duimianshan, and put forward two draft agreements. The second draft said: China and Portugal would conclude a commercial treaty including "articles that often appeared in treaties between China and other Western countries" and Portugal would co-operate in the opium revenue work of China. This draft avoided the Macao problem; China gained Portugal's co-operation in levying opium tariff and tax, while Portugal got the commercial treaty with China it had long desired. Henceforth, Portugal could enjoy various privileges, like unilateral most-favoured nation treatment and extraterritoriality. But the Portuguese hoped for acceptance of the first draft. The key difference was a clause that read:

In this draft, China admitted that Macao and its dependencies were almost equivalent to being a Portuguese colony. Because the second draft did not serve Britain's purpose, Hart persuaded the head of Grand Ministers of the Foreign Office, Yikuang, and others to adopt the damaging first draft rather than the milder second one. He argued that Macao had been occupied by Portugal for a long time already. Even if we did not allow them to reside perpetually, it would be an empty talk. Moreover, Portugal was getting poorer and poorer, and the big powers like Germany, Russia, France, the United States and others all wanted to buy Macao to station their troops there. That would be even more worrisome. China could neither prevent the sale, nor permit it. Therefore, it was most important to have the article about Portugal "never alienating Macao to a third country".

Before long, after reaching agreement about preserving the customs stations outside Macao, the Qing government directed Campbell to sign the protocol. Even then, Gomes and some other Portuguese officials still thought that the status of Macao was not so clear-cut in the protocol. At the time of signing, they went so far as to add "as any other Portuguese possession" into the clause of "the perpetual occupation and government of Macao and its dependencies by Portugal", further bringing the colonial nature of Macao to light. Without asking for instruction from the Chinese government, Hart agreed to the revision. In March 26, 1887, Campbell signed the "Protocol of Lisbon" on behalf of Qing government. The protocol had four articles:

After the signing of the "Protocol of Lisbon" between China and Portugal, the Qing government set up Chinese Customs Offices near Hong Kong and Macao on April 2, 1887. The Macao Customs Office was located at Xiaomaliuzhou, on an island of Gongbei Bay, so it was named the Gongbei Customs Office. The establishment of the two customs offices was favourable to the Qing government, and the establishment of Gongbei Customs later proved advantageous to Macao as well. But in order to make the Portuguese co-operate in levying the opium tariff and tax, the Qing government agreed to allow the Portuguese to occupy and govern Macao perpetually; such a game was indeed not worth the candle. When the contents of the Lisbon Protocol were made known in China, there was a public outcry in the court and among the commonalty.

Among the officials who made the strongest opposition was Zhang Zhidong, the Viceroy of the Two Guangs. Ever since taking over the viceroyalty, Zhang had paid close attention to the Macao problem. Besides his action of allowing the "weixing" gambling to be carried on in the interior, in the spring of 1886, when Shengyuan Zhang Yaochang and others of Mongha Village together repeatedly accused the Portuguese of forcing inhabitants to pay land and house taxes to them, Zhang Zhidong had delivered a note to the Portuguese authorities in Macao, demanding that they "not force the Chinese people to pay taxes to them". He had also sent officials to investigate the conditions of the Portuguese and checking the smuggling of silk cocoon into Macao at Zhini customs stations. When the negotiations with Portugal started, he opposed the closing down of the customs stations around Macao. After the signing of the protocol, he wrote a memorial to the throne with a different attitude, pointing out that letting the Portuguese perpetually occupy and govern Macao presented seven problems with severe consequences. As the protocol had already been signed, it was difficult to stop it now, so he put forward five measures to alleviate the damage. The main measures were:

First, when the final treaty was to be signed, the contents of it should be altered; in particular, the treaty had to include a declaration that although the Portuguese were allowed to reside in Macao perpetually without rent, Macao was still China's territory and not a Portuguese possession, and Portugal was not allowed to transfer it to any other country.

Second, the land leased by the Portuguese had to be clearly delimited, and according to the international law that the land owner had the right to govern the waters, the waters around Macao had to be ruled by China; the Portuguese could not administer any waters.

Third, the Chinese version of the protocol and the Western language versions were not identical. In particular, in the Western versions, "Macao" was all called "Macao and its dependencies", which did not conform to the contents of the memorial of the Foreign Office to the throne. Therefore, the Chinese and Western language versions had to be checked carefully, so as to guard against deception and prevent China's territory from being further encroached upon.

Fourth, although the protocol had been concluded, the power of approval rested with the court. The approval of the formal treaty should be postponed until the tariff and tax revenue had greatly increased and the swindlers and escapees had been sent under escort whenever they were wanted. In other words, all stipulations had to have been proved effective before the final treaty was signed.

When Zhang Zhidong presented his memorial opposing the treaty, the Portuguese plenipotentiary Thomaz Roza had already set out for China. In late July, the two sides began to hold formal talks. According to Portuguese government's instructions, Roza attempted to enlarge the scope of "Macao's dependencies" to include all of Macao Peninsula south of the Barrier Gate and six or seven nearby islands like Green Island, Taipa, Coloane, Xiaohengqin and Dahengqin. The ministers of the Foreign Office of China were greatly taken aback. On the one hand, they hurriedly sent officials to Macao to investigate the actual situation; on the other, they telegraphed to Zhang Zhidong, asking whether the Chinese inhabitants' lawsuits south of the Barrier Gate were still tried by the local Chinese officials; how much grain and money of tax a year was actually levied from villages like Mongha; how much was levied by the Portuguese.

After investigation made by the Prefect of Canton, Sun Ji, and other officials, Zhang Zhidong and the Governor of Guangdong, Wu Dacheng, replied to the Foreign Office by telegram saying that Mongha Village with four qing (1 qing = 6.6667 hectares) of land paid over 30 taels of silver of land tax to Xiangshan County each year, but had never paid any taxes and lamp fees to the Portuguese. As Long Tin, Long Wan and other villages had no arable land, they did not pay land tax to Xiangshan County; in regard to the taxes imposed upon them by Portuguese, some villages refused and some paid. The major lawsuits in the villages like Mongha and others, and even in the Portuguese settlement, were still handled by the Chinese officials of Xiangshan County.

Defying the opposition from the Foreign Office, Wu Dacheng himself took five gunboats and made a survey of Macao and the islands of Taipa, Coloane and others. Wu met the Portuguese Governor of Macao, Firmino Jose da Costa, three times, informed him of China's intention of making a clear delimitation of the Portuguese settlement, implying that China would take back the extra land occupied by the Portuguese. Wu also made Costa agree to cancel the house number plates put on forcibly in the Mongha and other villages. Then Wu met the inhabitants from the various villages and islands, asking them "not to quarrel or fight with the Portuguese because of their being bullied and humiliated in the past, so as not to cause new problems". The visit to Macao by the Governor of Guangdong moved the local Chinese inhabitants to tears. Wherever he went, they crowded around him with cheers, saying that they were absolutely unwilling to give away the place where they had lived for generations and let it be occupied and governed perpetually by the Portuguese.

Upon Wu's return to Canton, he and Zhang Zhidong presented separate memorials to the throne, pointing out that around Macao, some areas had originally been leased by the Portuguese, and some had been occupied only 10 or 30 years ago, while others had successfully resisted recent Portuguese attempts to occupy them. Now when concluding the treaty, the Portuguese "would certainly be greedy and try to fish the maximum in muddy waters". If the actual situation was not carefully examined, not only would large tracts of land be occupied by the Portuguese, but also future troubles would arise, such as the blockage of the seaways of the Western part of Guangdong, and the loss of Qianshan Stronghold's strategic advantage.

Wu and Zhang also pointed out that opium was shipped in from abroad to Hong Kong first, then redistributed to various ports; therefore, the key point to check opium smuggling was Hong Kong rather than Macao. Even if the Portuguese took part in the smuggling, the market in Macao was limited, and the Chinese government could easily prevent the smuggling both on water and land outside Macao. Therefore, it was not necessary for the sake of checking opium smuggling to let Macao be owned by the Portuguese. Moreover, the Portuguese co-operation was not necessary very competent. At the moment, they absurdly said that waters around Taipa and Coloane islands and the Cross Gate were administered by the Portuguese, preventing the Chinese customs from suppressing smuggling in these waters. Once these places were formally occupied by them, the blocking would be even more harmful, instead of being helpful; it was precisely detrimental to suppressing smuggling.

Zhang and Wu also suggested clearly delimiting the Portuguese settlement as soon as possible. The main points were as follows:

First, the old settlement wall should be restored and still be the demarcation line of the settlement area.

Second, the houses and gardens the Portuguese had already built between the settlement wall and the Barrier Gate, could be incorporated into the settlement area, but beyond that, not an inch more land was to be occupied.

Third, the Portuguese had to withdraw from the Barrier Gate, and the Chinese authorities should rebuild it and send troops to defend it.

Fourth, the office of the Vice Magistrate of Xiangshan County should be rebuilt near Monha Village, and the Vice Magistrate should be stationed there anew.

Fifth, Green Island should by no means be occupied by the Portuguese.

Sixth, places like Wanzai and Yinkeng which the Portuguese wanted to occupy should be regularly inspected by the local officials, so as to prevent their occupation.

Seventh, China should station troops at Taipa and Coloane. At most, the Portuguese could be allowed to temporarily lease and stay in areas where a fortress and several houses of them had been built.

Finally, Zhang and Wu stressed over and over again that since the Portuguese guns were old and their armed forces were weak, it was China's generosity alone that allowed them to remain. In return for China's generosity, the Portuguese would have to explicitly agree to stop their encroachment upon China's territory and rights. As to the treaty in negotiation, which would inevitably create serious troubles in the future, China should postpone its conclusion or cancel it.

Faced with the unanimous opposition of the top officials of Guangdong, the ministers of the Foreign Office did not want to conclude a treaty with Roza rashly. They told him: "China need not rely upon outside help in handling the opium revenue work", and reconsidered the formula of redeeming Macao. Alarmed and confused, Hart tried to persuade Roza to withdraw the clause in the draft exactly defining the scope of Macao's dependencies. He reminded Roza time and again that the most appropriate strategy was to sign the treaty with the wording of "Macao and its dependencies", believing that eventually, something favourable would take shape naturally. Meanwhile, Hart tried his best to cook up lies before the ministers of the Foreign Office, advocating the necessity of signing a treaty with Portugal. Even Hart himself admitted later on that he had adopted a mean method of deceiving the ministers of the Foreign Office.

Because Li Hongzhang favoured the concluding of the treaty and Zeng Jize opposed China's going back on her words before the Westerners, the ministers of the Foreign Office who had been hoodwinked by Hart decided to sign the treaty after revising about the Macao status clause in the draft, especially after deleting "its dependencies" and "as any other Portuguese possession" of the second article in the draft. One of their arguments was that the opium revenue work could not be fully implemented unless it was carried out with the co-operation of both Hong Kong and Macao. And their soundest argument was that Portugal was getting poorer and poorer, and other Western big powers such as France, Britain, Russia and Germany all wanted it as a place to anchor their warships and station troops. If Macao should be occupied by these powers, it would be even more harmful. Since China was unable to retrieve Macao, it might be an opportunity to reach an agreement with Portugal, making Portugal promise not to transfer Macao to a third country, so the future troubles might be uprooted. This was the most important purpose of the treaty.

As to the boundary of Macao, the ministers of the Foreign Office thought that if the delimitation was to be made clear now, it would inevitably lead to disputes that might block the treaty. They considered things would be even more worrisome and thorny, if certain incidents should be stirred up, and if Portugal should seek help from some big powers through secretly colluding with them and these powers should interfere the negotiation.

Therefore, these ministers decided not to delimit a boundary of Macao for the time being; a special convention concerning the boundary of Macao was to be made after appropriate talks by officials from the two countries, and before that "neither side should make any alteration". By so doing, they thought that even if the boundary could not be delimited for a while, no discord would appear now, and no more land would be encroached upon.

Finally, through discussing the matter over and over again, and after reaching agreement on the extradition of Chinese criminals from Macao, the Qing government appointed Yikuang and Sun Yuwen as plenipotentiaries. The "Treaty of Peking" including 54 articles and three articles of appendant convention about the suppression of opium smuggling were signed on December 1. The articles concerning Macao status read as follows:

Roza feared that the Qing government might go back on its words because of the opposition from its officials, so he hurried to Portugal with the document, had it ratified and sealed by the Monarch, and then hurried back to China with the greatest speed and exchanged the treaty with Li Hongzhang, the Minister in Charge of the Treaty Document Exchange, on April 28, 1888 in Tianjin. The Portuguese had finally obtained the treaty they had been expecting for decades.

The fact that the Qing government should have consented to conclude the Treaty of Peking with Portugal was another sign of its muddleheadedness and decadence. At the time of final conclusion of the treaty, the ministers of the Foreign Office already knew that it was not of much significance to have Portuguese co-operation in checking opium smuggling. Their consent to Portugal's perpetual occupation and government of Macao was mainly to get a promise not to alienate Macao to a third country from Portugal, so as to prevent other Western big powers from getting possession of Macao. It was that consideration rather than the consideration of the opium tax revenue work that the ministers considered the most important purpose of concluding the treaty.

Actually, through the Westernization Movement in the late 19th century, the Chinese army had already shown some combat effectiveness in repelling the Russian invasion in Xingjiang and in the Sino-French War, cowing the Tsarist troops invading Xinjiang, and inflicting heavy losses upon the French expedition army invading Vietnam and China. It was obvious that Western countries like Russia and Germany would not rashly buy the illegally occupied land from the Portuguese, and the Portuguese born in Macao would not agree to sell their native place to other countries either. Even if the Portuguese had decided to sell Macao to others, the Qing government had the ability to stop it. In the Sino-Japanese War of 1894-95, the Chinese Army suffered a debacle. From then on, the Japanese occupied Taiwan and Penghu, and the Germans forcibly leased Jiaozhou, so did the Russians to Luda, the British to Weihaiwei and Kowloon, and the French to Guangzhouwan. The big powers now could occupy China's best military ports at will, so it became unnecessary for them to spend huge sums to buy Macao, which was choked with silt, from the Portuguese. It is clear that when the Qing government still had strength to confront the big powers, they had no way to buy Macao; when the Qing government was too weak to confront them, it could not possibly have stopped them if they had wanted to buy Macao. The stipulation that "Portugal engages never to alienate Macao without the agreement with China" was nothing but a scrap of paper. Therefore, it was a most absurd action for the Qing government to let the Portuguese occupy and govern Macao perpetually just for the sake of preventing the big powers from buying Macao.

Moreover, in the treaty there were articles which were bound to cause even more troubles in the future. First, because of Hart's tricks, although the second article of the Chinese version had deleted the wording of "its dependencies" and changed "perpetual occupation" to "perpetual residence" to refer to the fact that the Portuguese just resided in Macao, that article still confirmed the Article Second of the Lisbon Protocol "in its entirety", so such a revise in the Chinese translation was meaningless. The second article of the Protocol of Lisbon stressed that "China confirms the perpetual occupation and government of Macao and its dependencies by Portugal", which clearly showed that China still recognized not only Portugal's perpetual occupying and governing of Macao but "its dependencies" as well. Then the Portuguese colonialists had a treaty basis to encroach upon "Macao's dependencies".

Second, the treaty did not delimit the boundaries of Macao and "its dependencies", only stipulating that "so long as the delimitation of the boundaries is not concluded, everything in respect to them shall continue as at present, without addition, diminution, or alteration by either of the parties". So the Portuguese could use this period of no delimitation of boundaries to occupy Chinese land.

Third, in regard to Chinese criminals fleeing to Macao, the treaty stipulated ambiguously: "the Governor of Macao will continue to follow the existing practice, after the receipt of a due requisition from the Viceroy of the Two Guangs". As to what was the "existing practice", the treaty did not go into details, which provided the Portuguese authorities in Macao an excuse to refuse to transfer criminals, turning Macao into an asylum for Chinese criminals.

This unequal treaty, though engineered and promoted by the British behind the scene, on the whole, instead of being forced by the big powers, was signed by the Qing government of its own accord. It caused serious damage to China. Nevertheless, in spite of the fact that the Qing government allowed the Portuguese to occupy and govern Macao perpetually, and almost lost the sovereignty over Macao, causing Macao nearly to be a Portuguese "colony" with this unequal treaty as its basis, there were still some differences between Macao and Hong Kong, ceded to the British. First, Macao had not been ceded to Portugal; it was still China's territory. Even the Portuguese foreign minister of that time claimed that the Portuguese had never said and did not intend to say that Macao was a Chinese territory ceded to Portugal. The Portuguese colonialists and their accomplice Hart just wanted to seize aggressive rights and benefits similar to cession but without the name; so they used ambiguous wording of "perpetual occupation and government" to fool the Qing government. Second, China retained the right that Portugal could never alienate Macao without agreement with China, namely, Portugal still could not dispose of this piece of land by exchanging, selling or ceding it according to its wishes, so China had not yet completely lost sovereignty over Macao. Third, Macao, as in the past, continued to enjoy preferential treatment as a domestic port of China and was never listed by the Chinese government as a foreign port. It is clear that the Westerners' and Chinese claims later on that "China ceded Macao in 1887" or "China leased Macao to Portugal perpetually" are both inaccurate.

After the signing of the Treaty of Peking between China and Portugal, knowledgeable Chinese officials opposed this treaty of national betrayal and humiliation, unanimously denouncing Hart's selling of China's sovereignty. In the past, because Hart seemed as if he had done something good for China in dealings with Britain and France, some Chinese officials took him for a good friend of China; but what he had done this time exposed his true colour. Liu Ruifen, a very careful person and China's envoy to Britain, France, Belgium and Italy, wrote in his diary, criticizing Hart:

Xue Fucheng, who was a famous commentator in current affairs and always abhorred Hart, published Yongan Wenbian (A Collection of Xue Fucheng's Works) in 1887, which included an article written several years before, "A Memorial to Premier Li Hongzhang on the Inappropriateness of Hart's Becoming the Inspector General of Customs". The article sharply denounced Hart:

After being taken in, the Qing government maintained some vigilance towards Hart, and from then on, Hart was no longer sent to conclude important treaties with Western countries on behalf of the Chinese government. In his late years, Hart seemed to be stung by conscience; he bore in mind constantly the idea of redeeming Macao from Portugal.

After the signing of the Treaty of Peking, the Guangdong authorities considered making the Barrier Gate the land boundary of Macao, and the middle of the navigation channel of the Inner Harbour the boundary on waters, by giving up the seven villages south of the Barrier Gate. By so doing, they could "conform to the treaty and did no harm to the Portuguese existing interests". However, some Portuguese colonialists took advantage of the unsettled borders to expand further, attempting to permanently occupy the area stretching from Jiuzhouyang Sea in the east, to Coloane and Dahengqin (D. Joao Island) in the south, to Wanzai and Yinkeng in Duimianshan (Lapa) in the west and to the foot of the hill behind Qianshan Stronghold in the north. The claimed area ran ten-odd kilometers from east to west, about 25 kilometers from south to north and 60-70 kilometers in perimeter.

In order to realize this plan of expansion, at the very year when the treaty between China and Portugal was signed, the Portuguese authorities in Macao moved buoys that set up in the Tongzhi Emperor period (1862-1874) from the middle of the navigation channel of the Inner Harbour to the shallow beach of Maliuzhou, claiming all of the waters west of Macao. Whenever Chinese ships anchored near Wanzai, the Portuguese would send small steamers there to check and register the ships and collect taxes. Once under the Portuguese administration, ships returning from other ports had to pay taxes in Macao, before they could return to Wanzai. Cost for the ships in Wanzai rose so high that they could hardly make any profit and had to move to Macao, causing the once prosperous town to decline quickly. The Portuguese also regarded Green Island, to the north-west of Macao, as their own. They leased part of it to a Chinese businessman to set up a cement factory in 1886, for 1,200 taels of silver a year. The Portuguese began to encroach upon Dahengqin and Xiaohengqin, attempting to make their occupation of the four islands at the Cross Gate an accomplished fact.

Portugal's expansion was vigorously resisted by the Guangdong authorities. Although the Viceroy Zhang Zhidong had failed to prevent the government from signing the Treaty of Peking with Portugal in 1887, he thought that since the border of Macao had not yet been fixed, China had no choice but to defend strategic points around Macao, so as to consolidate control of the coast. He ordered the civil and military officials and troops garrisoning the Xiangshan County seat and Qianshan Stronghold to strengthen the defences, improve their training, and not to leave their posts without permission. The garrisons were not just to hold on to the fortresses, but were to actually prevent the Portuguese further expansion. On orders of Zhang Zhidong, the Acting Vice Prefect of Coastal Defence, Xiao Bingkun, sent the troops north of Macao to garrison the coast from the Barrier Gate to Qiangshan, those west of Macao defend the coast from Wanzai to Yinkeng, those southwest of Macao to garrison Dahengqin, Xiaohengqin, Maliuzhou and other islands, and had the sea around Macao garrisoned and patrolled with warships. Li Zhongpei, the Acting Vice Battalion Commander of Qianshan Battalion, also stationed a tugboat north of Green Island, running parallel to the Barrier Gate, to prevent the Portuguese patrolling boats from encroaching upon the waters northern of Green Island. Zhang Zhidong also ordered the Vice Magistrate of Xiangshan County to move back from Qianshan Stronghold to Macao, so the influence of the Chinese authorities would be felt south of the Barrier Gate. Because the temporary county office at Beco dos Cotovelos had been destroyed by the Portuguese already, the Vice Magistrate had to lease a house from a Chinese inhabitant as his office. Thanks to these counter-measures, By 1888, the Portuguese expansion had not gained much ground.

After the signing of "Protocol of Lisbon" the first Inspector of Gongbei Customs E. Farrago, a Hungarian, who was very devoted to his duty, entered the area that the Portuguese authorities in Macao had wantonly declared to be Portuguese "territorial waters" to arrest smuggling boats. He had ferreted out several counterfeiters of Chinese currency, and discovered that the Portuguese authorities in Macao regarded issuing licences to counterfeiters as a source of revenue. His revelation made the Portuguese cut a sorry figure and they were very angry.

The Portuguese colonialists were not to be outdone. They created disturbances again. First, they attempted to make the Qing government recognize the two islands of Dahengqin and Xiaohengqin as dependencies of Macao. In the first half of 1888, when the Chinese officers and men rebuilt the thatched cottages into houses of bricks and tiles near Duoweishan on the Xiaohengqin Island, the Portuguese authorities presented a note to Zhang Zhidong arguing that Xiaohengqin was under Portuguese jurisdiction because the lepers living there were supported by them and accusing the Guangdong authorities of violating the treaty between China and Portugal. Zhang Zhidong sternly replied that Xiaohengqin had always belonged to the Xiangshan County and no Portuguese had ever lived in the Duoweishan area of that island. As to the Portuguese support for the lepers there, it was of common charity. How could one regard such an action as a proof of jurisdiction? For instance, every province in China had hospitals supported by foreigners. Could we regard these provinces as places of foreign countries? The Portuguese also tried to get the Grand Ministers of the Foreign Office of China involved, but Zhang Zhidong's persistency thwarted them.

Second, the Portuguese colonialists tried to encroach upon the area north of the Barrier Gate. At the beginning of 1889, when the Chinese army repaired the sentry posts around Beishan, the Portuguese set up a road lamp north of the Barrier Gate as their first step. Then they presented a note to Zhang Zhidong, claiming that the area from the north of the Barrier Gate to the ridge of Beishan hill used to be a neutral zone, and the setting up of sentry posts should be discussed by two sides. One side had no right to act arbitrarily. Zhang Zhidong gave them tit-for-tat. In his reply, he pointed out that the area north of Barrier Gate was solely under China's jurisdiction and the area south of the Barrier Gate did not all belong to Portuguese administration; only the area south of the Gate of St. Santonio belonged to Macao. The road lamp beyond the Barrier Gate had to be removed immediately. Seeing Zhang Zhidong's unyielding attitude, the Portuguese claimed in their note to the Foreign Office of China that the area from the north of the Barrier Gate to the ridge of Beishan Hill used to be a neutral zone. The Portuguese had administered the whole Peninsula of Macao, and the Chinese attempt to reduce the area of Macao where the Portuguese had resided was a wishful thinking. After hearing Zhang Zhidong's explanation, the Foreign Office pointed out in reply:

The Foreign Office also pointed out that in the wording of the treaty between China and Portugal, "so long as the delimitation of the boundaries is not concluded, everything in respect to them shall continue as at present, without addition, diminution, or alteration by either of the parties", was referred to the area from the Barrier Gate south to the Gate of St. Antonio. The area north of the Barrier Gate had nothing to do with the border problem mentioned by the treaty. If the Portuguese did not remove the road lamp beyond the Barrier Gate, the Guangdong authorities could also do something similar south of the Barrier Gate. The Portuguese knew that they were in the wrong, and saw that the Chinese army stood in combat readiness, so they had to dismantle the road lamp and stop encroaching upon the area north of the Barrier Gate temporarily.

Third, the Portuguese colonialists attempted to drive the Vice Magistrate of Xiangshan County out of the Macao Peninsula again, so as to occupy the whole area south of the Barrier Gate. Using the excuse that the Acting Vice Magistrate of Xiangshan County had quoted an old document from before the Opium War and used a derogatory term for foreigners to address the Portuguese, the Portuguese authorities attempted to drive him out, and the incident did not end until the Chinese gentry merchants in Macao intervened. Before long, by using the opportunity of carrying on negotiations about the road lamp incident, in a note to the Foreign Office of China, the Portuguese claimed that they heard that the Acting Vice Magistrate "had posted notice asking Chinese people to present lawsuits to him if they had been wronged". This accusation was an attempt to make the Chinese Foreign Office, which had a tendency towards compromise, withdraw the Vice Magistrate from Macao. Zhang Zhidong knew very well the significance of stationing the Vice Magistrate in Macao, and wrote to the Foreign Office, asking the ministers to brush aside the unreasonable Portuguese demand. As a result, the Portuguese plan came to nothing once more.

In the autumn of 1889, Zhang Zhidong was transferred to the post of the Viceroyship of Hunan and Hubei provinces. His successor was muddleheaded and conservative Li Hanzhang. The Portuguese colonialists were overjoyed. After Zhang Zhidong left Canton, besides expelling the Vice Magistrate from Macao, the Portuguese authorities immediately claimed that the waters north of Green Island, the Jiuzhouyang Sea and so on all belonged to Macao. They sent steamers to expel the Chinese armed tugboat stationed north of Green Island, and began to build a dike road linking Green Island with Macao Peninsula, so as to further control Green Island. In the meantime, they even asked the newly appointed Inspector of Gongbei Customs A. E. Hippisley, a Briton, to relay a map drawn by them to the Acting Vice Prefect of Coastal Defence, Cai Guozhen. The map falsely made Macao cover all the waters north of Green Island and even the land right to the wall of Qianshan Stronghold. Cai Guozhen held that if the Chinese armed tugboat should withdraw from the waters north of Green Island, the Portuguese would invade and occupy waters north of Macao and further encroach upon the Qianshan region. Therefore, on the one hand, he sternly refused their demands; on the other, he ordered the captain of the tugboat to keep a close watch over the sea. He ordered an armed steamer, "Jianrui", to reinforce the defence, and stationed another armed tugboat at Wayao Village in Duimianshan, opposite from Green Island, to reinforce each other and show that the Chinese army would fight for the place.

The Portuguese authorities was very angry. On May 6, 1890, they sent a warship and a small patrol boat with several dozen officers and men to the north of Green Island. The Portuguese soldiers boarded "Jianrui", seized the captain Li Changan by the chest, and claimed that no Chinese warship was allowed to anchor at the waters north of Green Island. Li Changan had to retreat to Qianshan. Cai Guozhen knew that the Portuguese authorities "would not necessarily content themselves with expelling our ships", so he further strengthened the defences north of the Barrier Gate. He dispatched two companies of soldiers to repair and garrison the batteries at Beishan and Latashi, which had been deserted since 1849, and one company of soldiers plus two tugboats to garrison the old battery at Shijuezui, across from Green Island. He also strengthened the naval force through recruiting soldiers and buying three speedy row boats. Then he prepared to station armed ships north of Green Island again. After hearing the news, the Portuguese authorities threatened that since the area from the north side of Green Island to Yaposhi of Qianshan belonged to Macao, if the Chinese naval ships should anchor there again, they would certainly drive them out as before. Meanwhile, they assembled the Chinese merchants in Macao and forced them to pay more fees as fund for a further strengthening of their military force.

Defying the Portuguese threat, Cai Guozhen led five armed ships himself and stationed these ships at north of Green Island on June 23. The Portuguese authorities sent a warship to threaten the Chinese ships, and ordered the fortresses in Macao to demonstrate their strength with gun fire under the pretence of practicing live ammunition maneuvers. Cai Guozhen took no notice. The Portuguese then presented a note to Li Hanzhang, falsely charging Cai with deliberately intruding into the waters of Macao. The Inspector of Gongbei Customs A. E. Hippisley, who was thick with the Portuguese, telegraphed Robert Hart and asked him to relay the message to the Foreign Office of China, fabricating a wild tale that "the armed rowboats of Qianshan Stronghold had anchored in the Inner Harbour of Macao".

Li Hanzhang reprimanded Cai Guozhen for "acting rashly" and "stirring up troubles and posing provocations". Li refused to support Cai with big warships, and telegraphed him to withdraw at once, saying: "If you should dare to defy the order deliberately and create trouble, you are bound to be punished severely." Cai brushed aside his personal fate, and pointed out in his reply: "if we withdraw, this sea lane will be lost forever", refusing to carry out Li Hanzhang's absurd order. Li Hanzhang was taken by surprise and asked the Circuit Intendant Shi Zaiyu and the Magistrate of Xiangshan County Li Zhiyong to go to Qianshan secretly to investigate. These two officials supported Cai Guozhen's opinion, but with the "mediation" of Hippisley, they decided to make a concession to the Portuguese, withdrawing the Chinese armed ships to the middle line between Yaposhi of Qianshan and Green Island, and agreeing that the ships on official duty of either side were not to go beyond this temporary line. But they clearly stated that the arrangement was only a temporary settlement of the dispute and had nothing to do with the future border delimitation. Although the Portuguese had pushed the water border northward, their plot to occupy the whole area north of the Barrier Gate failed.

After the Sino-Japanese War in 1894-95, with the excuse that pirates were appearing on Dahengqin and Xiaohengqin islands and the islands needed their protection, the Portuguese authorities built barracks on the two islands and put officials there to collect taxes on Chinese ships and goods. Only through representations made by Tan Zhonglin, the Viceroy of the Two Guangs, and with a compensation for the Portuguese buildings, did the Portuguese dismantle the barracks in 1897. In 1898, when the big powers had forcibly leased China's harbours and bays, the Portuguese seized the opportunity to force the villagers of Mongha to pay them land tax, which the villagers had refused to do for dozens of years. Finally, the Portuguese occupied and "governed" the whole Macao Peninsula. In 1900, when the Boxer Uprising had broken out in northern China, they even detained the Magistrate of Xiangshan County, Liu Shengfang, with the excuse that he had encroached upon the waters of Macao when he passed through the Inner Harbour by boat. By then, the area actually occupied by the Portuguese was much larger than that in 1887.

The next year, after the failure of the Boxer Uprising, the Qing government had to revise tax regulations of Chinese customs in Beijing together with the big powers. Because the Portuguese had no minister permanently stationed in Beijing. The Qing government invited the Portuguese government to send a special envoy to Beijing. The Portuguese, however, showed no interest in revising tax regulations; what they were concerned about was how to expand the area of Macao. At the end of that year, the counsellor Gabriel D'Ameida Sanctos, who had been slow in coming, requested the opening of the islands around Macao as trading ports from the Chinese Foreign Office. The Portuguese envoy J D'Azevedo Castello Branco, who arrived in Beijing in 1902, made more detailed requests about revitalizing Macao's commerce and dredging navigation channels. He especially wanted an official delimitation of the boundaries of Macao. At that time, the Portuguese colonialists already regarded the Macao Peninsula, Green Island, Taipa and Coloane as their own. They asked that the island of Duimianshan to the west of Macao, Dahengqin and Xiaohengqin islands to the southwest of Macao, be considered Macao's dependencies.

The ministers of the Chinese Foreign Office thought that the best approach was to pay no attention to the Portuguese request, and only pointed out that the islands along China's coast had always belonged to counties, subprefectures and prefectures; there had never been such a thing as one island belonging to another. Therefore, the border of Macao could only be delimited as at the present according to the treaty; there should not be any dependencies beyond the boundary. After many consultations, Branco said that he would like to shelve the delimitation problem temporarily and discuss the expansion of commerce first. The two sides agreed that the Chinese customs would set up a customs office in Macao to collect tariffs according to the new tax and tariff regulations, which was regarded as a clause to China's benefit, and the Portuguese and Chinese merchants jointly established a company to build a railway linking Macao with the capital of Guangdong Province (i.e. Canton), which was regarded as a clause that benefitted Portugal. Finally, in 1902, the two sides initialed the Peking Convention with nine articles and exchanged notes for the construction of the railway. Afterwards, the two sides initialed an Additional Convention about the Establishment of a Customs House at Macao at the beginning of 1903.

But after Branco's return home, the Portuguese cortes refused to approve the Peking Convention, giving the excuse that setting up a Chinese customs house in Macao would limit Portugal's sovereignty. At the beginning of 1904, Branco had to negotiate with the Chinese Minister of Commerce Lu Haihuan in Shanghai. After much pleading, the Qing government agreed to sign a new treaty with Portugal. The new treaty canceled the clause concerning the establishment of a Chinese customs house in Macao and stipulated that the opium shipped into Macao had to be kept at the official warehouse and the opium to be shipped to Chinese interior was not to be moved out until China's customs duties had been paid; China would station a special pontoon in Macao for the Chinese Gongbei Customs to check the various goods shipped in and out of Macao. Therefore, China's customs could still control the goods of import and export through Macao. As to the grain needed by Macao, the two sides reached a preliminary agreement that China would supply 300,000 piculs a year according to the population in Macao.

In the meantime, in view of the fact that the purpose of the Portuguese in wanting to build the Canton-Macao Railway was to "expand the border of Macao, attempting to occupy Xiangshan", the minister in charge of railway supervision, Sheng Xuanhuai, who had held talks with Branco, made many restrictions in "The Contract of Canton-Macao Railway". It was stipulated that the Sino-Portuguese Railway Company would be jointly set up by the merchants of the two countries, and the Portuguese government should by no means interfere in any of the matters concerning the company, so as to prevent the Portuguese from occupying Chinese territory by using this opportunity. Neither the new treaty nor the contract concerning the Canton-Macao railway enabled the Portuguese to expand the area of Macao. For that reason, the Portuguese neither approved the new treaty, nor invested any money for the construction of the railway. That was awkward for the Chinese merchants, who had already raised two million silver dollars as capital to build the railway. Later, the Portuguese government announced the canceling of the contract and the railway was never built.

Since they had failed to expand Macao's border through the agreements, the Portuguese authorities in Macao took a series of measures to continue their expansion. In 1905, they leveled the Chinese tombs around villages like Tap Siac, and threw the unknown skeletons into the sea. In 1907, they forcibly purchased the houses of over thirty households in the village of Long Tin, paying only thirty-odd taels of silver for a brick house and one tael for a thatched cottage. They beat up the villagers who refused to move, drove them out, and set their houses and cottages on fire. As a result, the ancient Long Tin Village was wiped out completely and the villagers were left destitute and homeless.

The Portuguese authorities in Macao also attempted to occupy the east part of Duimianshan. In June, 1907, they crossed the Inner Harbour and posted notices at Wanzai, forcing the Chinese fishing boats and ferry boats anchoring at Wanzai with Chinese licenses to purchase licenses from Macao within fifteen days. When boatman Huang Jianfeng and his colleagues refused to change their licenses, the Portuguese detained their ships and fined them fifteen silver dollars for each. The Portuguese authorities compelled the fishing boats getting an oil coating at Yinkeng Oil Mill to pay fees, or they would not be allowed to anchor there. A hospital at Wanzai run by the Chinese gentry merchants was also interfered with by the Portuguese doctors. They forbade the patients of a certain infectious diseases to be discharged from the hospital without their approval. Later on, due to the firm resistance of the local people and the Viceroy Hu Xianglin, the Portuguese failed to further expand around Wanzai.

From 1900 to 1907, the Portuguese authorities more and more openly violated the stipulations concerning the transfer of Chinese criminals in the "Treaty of Peking" between China and Portugal. In regard to escaped criminals, after receiving the note presented by the Viceroy of the Two Guangs, they refused to follow the existing practice of ferrying them out and handing them to the Chinese authorities. In 1900, all of China was shocked when the Portuguese government refused to transfer Jing Yuanshan to China, saying that they regarded him as a political offender. In 1904, when a corrupt Chinese official, Pei Jingfu, who had absconded to avoid punishment, was caught in Macao, two Chinese warships happened to be sailing to Macao; the Portuguese authorities alleged that "the Viceroy of the Two Guangs was demanding an immediate extradition by force", so they refused to try the case and confirm whether to hand over the criminal or not unless the Chinese warships left Macao. Around 1906, the officials and men of Xiangshan County and Qiangshan Stronghold arrested the notorious bandit chief Lin Peinan in Macao twice, but the Portuguese authorities refused to cooperate and released Lin Peinan both times. Therefore, Macao gradually became a shelter for escaped criminals from the interior.

Moreover, the Portuguese authorities purposely confused the Chinese who were either born in Macao or had lived in Macao before with the Portuguese. When these Chinese committed crimes in the interior, the Portuguese authorities in Macao demanded that these offenders should be handed over to them for trial. So many lawless persons went to Macao, gained Portuguese nationality, and then returned to the interior. When they were arrested in the interior, they could claim to be "Portuguese" and "escape from the net of justice under the protection of the foreigners". The most ridiculous case was that of an old man called Feng Qiji. Feng was born in Macao in 1834 and returned to his native place, Fanyu County, to live as early as 1850. He had been a Jiansheng (a scholar who studied in imperial school), had acted as the village chief and had been the person in charge of the sacrificial rites of his clan temple. But when he was put into prison because of some offence he had committed in 1901, he suddenly denied being Chinese, declaring himself to be Portuguese and entitled to all the attendant. The Portuguese authorities in Macao demanded Feng's extradition to Macao and made many representations to the Chinese authorities, arguing that he was Portuguese because he had been born in Macao.

In the light of such a situation, in a new agreement reached between the representatives of the two countries in 1904, there was a special clause about the Chinese who lived in Macao and joined the Portuguese nationality. It was so framed as to prevent those Chinese who had obtained Portuguese nationality "from improperly arrogating to themselves privileges that are reserved for Chinese subjects, such as the right of residence for purpose of trade in the interior or at ports not open to foreign trade" and others. This agreement was not approved, so the problem remained. On December 31, 1908, without consultation with the Chinese government, the Portuguese government promulgated "Macao Offender Extradition Regulations" of 24 articles, a series of stipulations about whether a Chinese offender in Macao should be transferred to the Chinese authorities or not. It claimed that a Chinese offender would not be transferred unless the offence he or she had committed conformed to the corresponding clauses in the Portuguese law. So the Portuguese authorities openly distorted the stipulation in the treaty between China and Portugal about the extradition of offenders. Once the inland offenders escaped to Macao, whether they were guilty or not and whether they were to be transferred or not, were all not to be decided by the Chinese law but by the Portuguese law.

During the twenty years after the signing of Treaty of Peking between China and Portugal, the Portuguese authorities in Macao never stopped their expansionist activities. They completely occupied the area south of the Barrier Gate and Green Island, and further encroached upon Taipa and Coloane islands. Nevertheless, due to the resistance of the Guangdong authorities and People, their attempt to occupy the area north of the Barrier Gate, the east part of Duimianshan, and the islands of Dahengqin and Xiaohengqin was successfully curbed.

In June 1907, after the Portuguese had intruded into Wanzai, the acting Viceroy of the Two Guangs, Hu Xianglin, asked the Foreign Office to send officials to survey the boundary of Macao. At the end of 1907, many Chinese merchants from Canton, Xiangshan, Hong Kong and other places again asked the Qing government to send officials to Macao to delimitate the boundary. Their call led to negotiations with the Portuguese about delimiting Macao's border. Before the Qing government had responded to these suggestions, an incident involving a Japanese ship pushed the dilatory top officials into quickly changing the policy about the Macao border problem.

The Qing government prohibited the common people from buying foreign weapons. Since the Portuguese authorities in Macao allowed the importation of arms, the profiteers shipped arms to Macao, and then smuggled them into the interior of China to reap staggering profits. It was estimated by foreign newspapers that in about ten years, the number of firearms smuggled into inland through Macao surpassed 500,000. Except for a few bought by the revolutionaries led by Sun Yat-sen. most of the weapons fell into the hands of bandits, who rose in swarms in the Guangdong area. The top officials in Guangdong were quite worried, and the British authorities in Hong Kong also strictly prohibited arms and ammunition from being shipped to Macao.

At the beginning of 1908, the top Guangdong officials learned that Chinese merchants from the Guanghe Shop in Macao were about to ship in 2,000 rifles and 40,000 bullets from Japan on the "No. 2 Shinmaru", a Japanese merchant ship, so they sent many armed ships to patrol the area around Macao. As large ships could not sail into Macao's silt-choked harbours, the "No. 2 Shinmaru" anchored two nautical miles east of Coloane Island while it was approaching Macao on the morning of February 5, and prepared to unload. The Chinese officers and men patrolling the sea area went aboard to check, and they found that the ship was going to unload the firearms onto the barges from Macao without Chinese authorities' import permission. According to the Chinese customs regulations, if foreign merchants carried firearms and other banned goods without permission, both the ship and the goods on board were to be confiscated. The Chinese officials and men detained the Japanese ship and lowered the Japanese flag the next morning. Eight days later, the Japanese Minister to China negotiated with the Qing government about the detention of the "No. 2 Shinmaru". The Japanese minister maintained that the shipment of firearms by the "No. 2 Shinmaru" ship approved by the Portuguese officials in Macao, and that the place where the ship had anchored was within Portuguese territorial waters. He demanded that the Qing government release the ship, make an apology, punish the officials concerned, and pay for the losses. The Portuguese government did not want to lose this unexpected opportunity, and joined the Japanese, clamouring the "No. 2 Shinmaru anchored in Portugal's territorial waters", "the detaining of the ship violated Portugal's territorial rights, damaged Portugal's sovereignty, and impeded Macao's commerce". The Qing government repeatedly quoted international law and refuted these fallacies, pointing out in no uncertain terms that there was no such thing as "Portugal's territorial waters" around Macao, that the area where the "No. 2 Shinmaru" had anchored was within Chinese territorial waters, and that to load and unload goods at that place had to require permission from the Chinese Gongbei Customs.

With a presumptuous and arrogant attitude, the Japanese government flatly refused a Chinese proposal to have a joint hearing of both sides according to the Chinese customs regulation and asking a British admiral to make an arbitration. The Japanese minister even clamoured for war. The Qing government was forced to give in, accepting all the terms put forward by the Japanese. After this incident, the indignant Chinese people of the whole nation launched the first boycott of the Japanese goods. Some Chinese top officials also saw the harm of not fixing the border of Macao, and called for an early delimitation of the border of Macao. The Qing government finally decided to hold negotiations with Portugal as soon as possible.

As soon as the negotiations concerning the "No. 2 Shinmaru" had ended, the Qing government sent Gao Erqian, a former senior staff member of the newly established Ministry of Foreign Affairs, to Guangdong to investigate the incidents relevant to Macao, and asked the Portuguese government to send officials to negotiate. The Chinese government also demanded that the Portuguese government strictly prohibit people from trafficking in firearms and shipping them into Macao. Viceroy Zhang Renjun increased the troops at Wanzai, Qiangshan and other places to prevent further Portuguese encroachment. The Portuguese government agreed to prevent the common people from shipping firearms into Macao without permission, and appointed the Portuguese officials in Macao as representatives to negotiate the border delimitation with China. But the Portuguese Government described China's increasing armed forces in Wanzai, Qianshan and other places as "deploying troops within Macao area", and asked the British to mediate the so-called "Chinese troops' intruding Macao incident". The Chinese top officials in Beijing thought:

So the Ministry of Foreign Affairs telegraphed Zhang Renjun, instructing him not to withdraw the troops for the time being. In the meantime, because the representatives to negotiate the border delimitation appointed by the Portuguese government were the very officials in Macao who had been vigorously engaged in expansion, and who were not on good terms with the people and officials of Guangdong, the Qing government demanded that the Portuguese government appoint others.

The Portuguese authorities in Macao were very angry. They spared no effort in opposing the officials from Guangdong recommended by Zhang Renjun as the Chinese representatives, and stepped up their openly aggressive activities. They sent people to Dahengqin Island to force the Chinese inhabitants to pay land tax, arresting and detaining the inhabitants. They sent technical personnel to survey the sea around Macao, and placed orders for equipments, preparing to dredge the navigation channels to Macao within China's territorial waters. In order to demonstrate their strength to the Qing government, they assembled a frigate and several gunboats from Lisbon and Mozambique. Some of the warships even anchoring at Yinkang of Duimianshan.

Defying the threats of the Portuguese authorities, Zhang Renjun took emergency measures, such as sending a large number of well-trained troops to the area around Macao, and deploying the warship "Guangli" at Yinkang. The secret societies in Guangdong also assembled their forces, and made plans to fight against Portuguese aggression. Wu Yuzheng, Wang Xian and other overseas Chinese merchants who had returned to the mainland decided to build "Xiangzhou Port" in the deserted area north of Macao to absorb overseas Chinese capital and develop commercial business, like taking away the firewood from under the cauldron, so as to resist the Portuguese. The merchants' action was supported by Zhang Renjun and other Guangdong officials, and later on they asked the Qing government to approve Xiangzhou as a "free port".

The Portuguese authorities in Macao became a little worried. They asked their British allies in Hong Kong to back them up when necessary, and requested the British Minister to China help them. After the British officials' mediation, the Qing government telegraphed the Chinese Minister to France and Spain, Liu Shixun, sending him to Lisbon to negotiate with the Portuguese government to prevent a crisis. After repeated negotiations, the two sides orally agreed on five points:

The Qing government objected to the Macaonese officials' becoming surveyors, while the Portuguese side also did all they could to criticize the Guangdong officials. Therefore, the Qing government decided to appoint Gao Erqian, who had been promoted to Jiaosheshi (official in charge of negotiations) of Yunnan Province, as the minister in charge of Macao border delimitation, and the Portuguese government appointed Joaquim Jose Machado, who had been a senior official in one of the African colonies, as the commissioner for border delimitation. The place of negotiation was Hong Kong.

The people of Guangdong showed great concern about the coming negotiations. The Guangdong Autonomous Society, which was established when the Qing government was going to adopt a constitution a few years ago, was actively engaged in discussing the Macao border problem, making it known to the whole country and exerting efforts together with the whole nation to back up the government. On March 8, 1909, three hundred representatives from all walks of life of Xiangshan County assembled at Beishan Township to show concern about the Macao border delimitation. At the conference, the "Xiangshan Association Backing Border Survey and Delimitation" was set up. Soon afterwards, the "Guangdong General Association Backing Border Survey and Delimitation", formed by people from all walks of life, was established in Canton with branches set up in Hong Kong and other places.

Through studying international law and collecting proofs, the General Association and Guangdong Autonomous Society assembled to discuss the matter many times. They unanimously passed a resolution supporting a formula that on land the border should be the Portuguese settlement wall, while the sea should all belong to Xiangshan County. They expressed their determination to defend this line to "the bitter end". As to the question of how to deal with the Portuguese colonialists' expansion, they also put forward a number of suggestions, which can be boiled down into two:

First, the Chinese authorities should resolutely close the Barrier Gate and take measures to ban the selling of food to the Portuguese, ask the Chinese residing in Macao to go to Xiangzhou, and to keep the Chinese from going to Macao to gamble, visit prostitutes, smoke opium and so on.

Second, because the Portuguese authorities in Macao had violated the article of "no alteration of the border before its delimitation,", having steadily eaten up China's territory, the Chinese government should abolish the Protocol of Lisbon reached in 1887, canceling the Portuguese rights of "perpetual occupation" of Macao, and should make the Portuguese pay the land rent again. If they should dare to resist, much tougher measures could be taken.

The activities of the two non-governmental organizations won the extensive support from the Guangdong authorities, the people all over China and overseas Chinese. Within two to three months, the two organizations received 123 telegrams from China and abroad, expressing support for their arguing strongly on just grounds. The Portuguese authorities in Macao were very angry. At first, they demanded that the Qing government ban the General Association Backing Border Survey and Delimitation and the journal "Xiangshan Xunbao" (published every ten days), because the association and the journal called on the people to care about the Macao border problem. Later on, they falsely accused the Guangdong Autonomous Society of "preparing a sudden attack on Macao", threatening to have the Portuguese warships come back to Macao again. After getting reports from Zhang Renjun and other officials, the Qing government flatly refused the groundless request in a written reply to the Portuguese Minister to China, pointing out:

In the meantime, being afraid that the Chinese merchants in Macao would respond to the call to leave Macao for Xiangzhou, the Portuguese in Macao had to change their discriminating attitude towards the Chinese inhabitants a little. Portuguese merchants pointed out over and over again in meetings that without the Chinese, Macao would be just like a body without a soul and could hardly survive. The Portuguese, they said, should stand for an improvement of relations with the Chinese in Macao. These merchants said that they would like to see to it that the Chinese in Macao felt satisfied, asking the Portuguese government to improve politics, and to help the Portuguese authorities in Macao to revitalize its commerce, so as to retain the Chinese inhabitants. The Portuguese Governor of Macao also had to say that he would try his best to improve things concerning the requirements and interests of the Chinese. He revised some regulations that had discriminated against the Chinese inhabitants, and asked the Portuguese government to approve a special code concerning Chinese customs. The code stipulated that in civil affairs, the Chinese inhabitants could follow their own traditions rather than adopting Portuguese ways of life. The struggle against the Portuguese colonialists by the inland people helped the Chinese inhabitants in Macao to raise their social status.

On July 15, 1909, Gao Erqian and Joaquim Jose Machado started the border survey and delimitation negotiations in Hong Kong. At the very beginning of the negotiations, Machado handed over to Gao Erqian a series of documents. These papers claimed that in accordance with the generally acknowledged facts in Portuguese and world history, the Portuguese had gone to Macao in 1557. At that very time, pirates led by Zheng Zhilong were harassing and wrecking ships and villages along the coast of Southern China. The Portuguese drove them out and occupied the pirates' area as base for business. It was an established fact that at that time, Macao, the islands and the waters in the adjacent area, were under the control of the pirates. The place where the Portuguese settled down was a no-man's land, and they did not see any actual Chinese administration there. He also claimed that Macao should include the whole Macao Peninsula south of the Barrier Gate, islands and islets like Green Island, Taipa, Coloane, Dahengqin, Xiaohengqin, Duimianshan and others and the adjacent waters, with the area from the Barrier to the hill ridge of Qiangshan as a neutral ground. This whole area of 326 square kilometers, not only covered the settlement leased by the Portuguese hundred years ago, and the newly occupied area north of the settlement and south of the Barrier Gate, including three islands, but also included the area of Dahengqin, Xiaohengqin, Duimianshan and many other islets that the Portuguese had not yet succeeded in occupying.

Gao Erqian thought that only Macao had been leased to the Portuguese, not the islands. He pointed out: "how could the Portuguese make these islands part of Macao without the approval of China?" It was easy, he believed, to refute the terms of international law quoted by the Portuguese as their justification for occupying the islands; the difficulty lay in the undefined term "Macao and its dependencies" in the treaty signed between China and Portugal in 1887. Upon receiving Gao's report, the Ministry of Foreign Affairs decided to survey the original border and to make it the border of Macao. Other areas that had been occupied by the Portuguese early on could be recognized as "dependencies", so as to show that China did not go back on its word. On the other hand, they thought that the two islands of Taipa and Coloane had only had a tiny area occupied by the Portuguese, so "how could one use it as a proof of the Portuguese occupation of the whole of two islands ?" If there was no other way out, "the area could be exchanged with a place of the same acreage near the Portuguese settlement as a last resort."

When Gao Erqian negotiated with Machado according to these guidelines, Machado claimed that the whole Macao Peninsula had belonged to Portugal already when the Ming government built the Barrier Gate at Liahuajing in 1574, brazenly denying the historical fact that the Portuguese had leased Macao from China and paid land rent for nearly three hundred years. As proof of Portuguese sovereignty, he cited the bulletins the Portuguese authorities had posted in the Chinese villages they had broken into, the receipts of land tax they had extorted from the Chinese inhabitants, and the forts and roads they had built outside the Portuguese settlement in successive years. As telegrams poured in of telegrams from China and abroad, unanimously opposing further compromise, Gao Erqian decided to indefinitely postpone the negotiation, when he saw that there was no hope of taking back Taipa and Coloane from the very beginning of the negotiations.

While the negotiations were deadlocked, a tense confrontation between the Chinese and the Portuguese emerged in and around Macao. In order to make a show of force, the Portuguese assembled more warships and increased the troops in Macao from 400 to 700. The Portuguese created one disturbance after another, and provoked the Chinese people. At the end of July, a Portuguese armed ship and a team of small boats intruded into China's inland river northwest of Macao. Cruising and surveying in the daytime, at night they anchored near the river bank of Nanping Township, north of Duimianshan, and disturbed the local people with search lights. On August 21, the Portuguese authorities ordered the villagers of Mongha to dismantle all their houses within one week. Responding to this provocation, the Xiangshan Association Backing Border Survey and Delimitation convened a special session, and passed "The Charter for the Militia Troops Set up Jointly by Ninety-eight Townships", announcing that in order defend themselves, they were determined to take up arms against the Portuguese. They would purchase firearms as quickly as possible so as to establish a militia defence force uniting all the townships. Soon afterwards, they asked the Qing government to send additional infantry and naval troops to garrison the passes around Macao to blockade Macao. And an economic blockade, they hoped, would choke the Portuguese. The representatives of the Association Backing Border Survey and Delimitation also openly criticized Gao Erqian for looking down on the people of Guangdong and answering their demands with vague words. Gao Erqian felt that "with the people's emotion as strong as torrents, a tiny slip might cause an incident". He had to be more cautious in negotiations.

In an attempt to break the deadlock, Machado on the one hand suggested that the border problem be submitted to the Hague international court for arbitration; on the other, he threatened that the Portugal would pass Macao to someone else to lure the British to intervene and force the Chinese government to give in. Under the influence of the masses in Guangdong, Gao Erqian was strongly opposed to the arbitration of Macao border problem by foreign powers. He pointed out in his report to the Ministry of Foreign Affairs that Britain, France and Netherlands had common interests with Portugal. If the Macao border problem were given to them to arbitrate, they would be bound to be partial towards the Portuguese. Inevitably, China would lose. If it was dealt with through consultation between the two sides, there was still the hope of winning half of the game.

Although the Ministry of Foreign Affairs agreed with Gao, the British minister convinced them not to delay any longer. The Foreign Ministry instructed Gao to proceed with the negotiations exchanging Long Tin and Mongha for Taipa and Coloane, and at most allowing the Portuguese to keep the area already occupied by them on Taipa and Coloane as "private property" to "be used as a stopover", on condition that the places should not be regarded as dependencies of Macao. But the negotiations continued to stall. Machado, therefore, suggested Gao that they have an informal talk, with the real purpose of putting forward Portugal minimum requirements, to probe China's reaction. In the informal talks, Machado said that he could agree that Duimianshan, Dahengqin and Xiaohengqin belonged to China, but the Portuguese wanted to have a piece of land on the coast of Duimianshan. Gao did not agree to give away the land on Duimianshan, which the Portuguese had never occupied, but he consented not to build forts there, and to let Portugal occupy the whole Macao Peninsula and the three islands of Taipa, Coloane and Green Island. In the end, however, because Machado wanted the whole Inner Harbour, the negotiations ended without success.

The Ministry of Foreign Affairs was dissatisfied with Gao's way of handling the negotiations. In a telegram, the Ministry criticized him for failing to follow the established negotiation guideline: this border delimitation had to be based on the area of Macao itself. Otherwise, the Portuguese would reach out for a yard after taking an inch and there would be no end of it! Afterwards, the Ministry of Foreign Affairs again pointed out that although Green Island, Taipa and Coloane had been under the Portuguese control for a long time, they were occupied by the Portuguese illegitimately, and should not be ceded on the grounds of their occupation. The Portuguese were at their wits' end, and had to threaten the Qing government by singing the old tune that if Portugal had no other alternatives, he would have to give Macao to other country.

However, it was no longer 1887, when Yikuang and Li Hongzhang were deciding China's foreign policy. Many Chinese officials had seen through the Portuguese tricks, and pointed out at the Court that there was no need to make further concessions to the Portuguese. Supervising Secretary Chen Qinggui wrote in a memorial to the throne that since the Portuguese would not yield, if China wanted to settle the problem in a hurry, what China would lose was bound to be enormous. It would be better not to decide the matter for the time being, so that the Portuguese arrogance might be reduced. Meanwhile, the government should also help the merchants to develop Xiangzhou Port so as to divert profits from Macao. Then the Portuguese would have to give in at the end. These views were accepted by the Chinese government and in the light of the guideline of the government, Gao ended the negotiations, which held nine formal meetings and lasted four months, on November 13, without success.

Afterwards, Machado rushed to Beijing and asked the Qing government to agree to submit the Macao border problem to the Hague international court for arbitration. The British Minister to China also put pressure on the Qing government, claiming that international arbitration was an impartial way to solve the problem. If China did not agree, it would further show that the demands of the Portuguese were justified. The Chinese officials could foresee the outcome of such an arbitration, and they pointed out to Machado that the delimitation problem of Macao was a matter between China and Portugal, and that international arbitration was unnecessary. The Portuguese and British failed to lure the Qing government into a trap with the so-called "international arbitration".

After the breakdown of the negotiations, besides sending warships to the Inner Harbour of Macao from time to time and interfering in the Guangdong authorities' pursuit of bandits on the Xiaohengqin Island, the Portuguese authorities violated the agreement reached between Gao Erqian and Machado about mutual consultation on the dredging of the navigation channel, beginning to prepare for the task on their own. It was true that the channels needed to be dredged, but one of the purposes of their actions was to demonstrate their jurisdiction over the waters around Macao. The people in Guangdong were boiling with rage; quite a few even advocating an armed attack to retrieve Macao.

The Portuguese authorities knew that they were no match for the Chinese army and people, so they again asked the British government to intervene. In March and April of 1910, the British Secretary of State for Foreign and Commonwealth Affairs and others met with the Chinese envoy to Britain Li Jingfang several times. They claimed that China should not take any action against Macao. If China did, the Portuguese government would ask the British government to make good its promise, and then the British government could not simply stand by with folded arms. If China should invade and bully Macao without any provocation from the Portuguese, because of the agreement between Britain and Portugal, the relationship between Britain and China might break. Just At that time, the Qing government was negotiating with British government about the Kaiping Mine, which had been acquired through deception by British capitalists. The Qing government implied that China would make some concessions on the Kaiping problem, if Britain would not side with the Portuguese. The British did not want the relationship between Britain and Portugal to be affected, so they continued to claim that if Macao were "invaded", Britain would send troops to protect it. They asked China and Portugal to continue the border talks.

The Qing government was afraid of armed British intervention, and instructed the Guangdong officials to suppress the Guangdong people "so as to maintain the status quo and to avoid troubles that might give the Portuguese an excuse." The Viceroy of the Two Guangs Yuan Shuxun was full of misgivings and reacted absurdly to a highjacking incident on Coloane Island, arousing strong dissatisfaction among the people of Guangdong. At the beginning of July, 1910, pirates on the Coloane kidnapped ten-odd pupils of Xinning County, demanding that the parents hand over 35,000 silver dollars within two weeks, or they would kill the hostages. The parents reported the incident to Yuan Shuxun at once. But Yuan Shuxun hesitated, because the border of Macao had not yet been delimitated, he could neither present a note to the Portuguese Governor of Macao, as that would be regarded as recognizing the island to be Macao's "dependency", nor send troops to arrest the pirates, for that might cause troubles between China and Portugal.

The parents had to report the incident to the Portuguese authorities in Macao. Without presenting a note to the Chinese authorities, the Portuguese authorities immediately sent troops on to the island to pursue the pirates. After an initial defeat, with several officers and men killed or wounded, the Portuguese soldiers fired at the villages on the island with guns from the warships for several days, set fire to the houses on the island, and even bombarded and sank the fishing boats being used by the villagers seeking asylum. As a result, although the Portuguese rescued some hostages and arrested some pirates, a large number of innocent villagers were massacred.

After this incident, the people in Guangdong and overseas Chinese vehemently criticized the Portuguese authorities in Macao, and demanded the retrieval of Macao. They also sharply criticized Yuan Shuxun for "giving up sovereignty" and "leaving the inhabitants on Coloane to be slaughtered by foreigners". In dire straits, Yuan Shuxun was forced to condemn the Portuguese for using force without authorization on Coloane Island, which was not governed by Portugal. Before long, with an excuse of illness, Yuan resigned so as to apologize to the people of the nation, and asked the government to delimitate the Macao border as soon as possible to avoid future troubles. Afterwards, Liu Shixun, the Chinese envoy to France and Spain, took over the Macao border problem. He arrived in Lisbon in the late September, 1910, and prepared to hold talks with the Portuguese government. But a revolution to overthrow the feudal monarchy broke out in Portugal at the beginning of October 1910. The Macao border problem was not a priority for the new Portuguese Republic, so the negotiations were postponed once more.

The establishment of a republic in Portugal gave some Chinese people the confidence that the Macao problem would be solved. On November 17, the Association Backing Border Survey and Delimitation in Canton, Xiangshan and Hong Kong all held special sessions, and decided to present a petition to the Qing government, demanding to abolish the old treaty and retrieve Macao. At the same time, they began to collect funds to improve the militia, and they were ready "to stake the retrieving of Macao on one battle". At the end of the same year, at the conference held by Guangdong Political Consultation Assembly (Zizhen Yuan), members of the assembly also made an appeal to the Qing government, saying that since Portugal had changed its state system, China had good grounds to abolish the treaty of 1887, take back Macao and make Macao a trading port. Finally, the assembly passed a resolution pointing out that it was necessary to revise the treaty with Portugal, canceling the wording of "Macao's dependencies" in the treaty, so that the Macao border delimitation problem could readily be solved.

Unfortunately, the newly established Portuguese republican government inherited the mantle of the old monarchy, refusing to give up the colonialist policy. In Macao, with the support of the British, the Portuguese authorities stuck to their policy of expansion. At the beginning of 1911, they even started dredging the Inner Harbour, and signed a contract with a British company to dredge the sea north of Taipa. In the meantime, the Portuguese authorities presented an ultimatum to the Guangdong authorities, denying Dahengqin and Xiaohengqin were Chinese territories and forcing the Guangdong authorities to withdraw troops from the two islands, which caused an public outcry in the whole province of Guangdong.

In April, the Association Backing Border Survey and Delimitation of Xiangshan County presented a letter to the Qing government asking the government to station troops at the forts of Wanzai, Qianshan and others and to arm the militia, to prepare to fight the Portuguese. Meanwhile, the association requested the new round of border delimitation talks be held in Canton, and that both Guangdong officials and the representatives of the association should take part in the talk, so that success could be ensured. These opinions received warm response from people of all walks of life. The Guangdong Political Consultation Bureau passed a supporting resolution immediately.

But at that time, the Qing government was in the midst of a raging revolutionary storm. In order to conform to the public opinion, the Qing government agreed to give full authority to the Viceroy of the Two Guangs, Zhang Mingqi, who had an unyielding attitude towards the Portuguese, to handle the border problem. Zhang repeatedly sent representatives to talk with the Portuguese authorities, and had the senior officer of the 25th Division, Huang Shilong, to inspect the defences of the Chinese army around Macao. In accordance with Huang's formula of controlling Macao with both military and commercial means, Zhang on the one hand, presented a note to the Portuguese authorities in Macao demanding an immediate stop to the dredging; on the other, he issued firearms to the militia of Xiangshan County and increased the new type of troops who were equipped with Western arms and trained in Western ways in places like Qianshan Stronghold. Qianshan now kept one thousand men and four warships.

The Portuguese were terrified. They hurriedly transferred more warships, moved more troops to Macao and appealed to the big powers for help. On August 30, the consuls of the big powers to Canton requested a meeting with Zhang Mingqi, offering to "mediate". Zhang Mingqi solemnly pointed out: The matter about the new army, which has been trained in Western ways, armed with Western weapons and stationed at the border of Macao, was something concerning China's defence and sovereignty. It was impossible for us to withdraw these troops.

Under such circumstances, even the British were afraid that the Chinese would attack Macao, because of long accumulated grievances. The British advised the Portuguese authorities in Macao to stop at the brink of the precipice, and dredging halted at the end of August. With that, the two sides should have resumed the border delimitation talks, but for the revolution overthrowing the Qing dynasty broke out soon afterwards, and the Macao border problem remained unsettled.

With the harbour undredged, Macao had no way to shake off its economic doldrums. In the meantime, the Chinese army and people had enhanced their alertness in places of Wanzai, Yinkang, Dahengqin, Xiaohengqin and others, so it was difficult for the Portuguese authorities to continue to nibble at the Chinese territory near Macao. The unsettled border was not so advantageous to the Portuguese colonialists as it had been in the 19th century.

In order to end this situation, the Portuguese government repeatedly requested delimitation of the land and water borders of Macao from the new Republic of China, the Chinese Ministry of Foreign Affairs sent officials to Guangdong in 1914 and 1915 to investigate the borders, and telegraphed Gao Erqian, inquiring about the negotiations in the past. But because the Portuguese insisted on the aggressive terms put forward by Machado, no new talks were held. Afterwards, the Portuguese authorities in Macao attempted many times to dredge the harbours and reclaim the beaches, but they were forced to stop because of the objections of the Chinese government and people. In 1919, seizing the opportunity of confrontation between the Southern Government and the Northern Government in China, the Portuguese authorities reclaimed land from the sea, increased troops, built defence works, and prepared to confront with the Southern Government of China with force. The Southern Government thought:

At the beginning of 1920, besides the army that had already been dispatched, the Southern Government of China sent the warships "Lei Long" and "Yong Feng" to Jiuzhouyang Sea to force the Portuguese to stop dredging. Afterwards, the Southern Government refused the Portuguese suggestion of holding border delimitation talks, but finally approved their request to dredge the navigation channels and signed an agreement with the Portuguese allowing them to carry out the Macao harbours project. In return, the Portuguese had to implement the revised port regulation of Macao and regulations about the transfer of Chinese criminals from Macao to the Chinese authorities. In these regulations, certain restrictions on the wanton Portuguese behaviour were made.

In 1921, at the "Pacific Conference" held in Washington, the Portuguese delivered a memorandum about the Macao problem, attempting to make the big powers intervene. Meanwhile, in order to show that their area of jurisdiction included Duimianshan, the Portuguese navy interfered in the Chinese troops' pursuing bandits at Yinkang, and even fired at the Chinese army. The Chinese army's counter-attack left four Portuguese seamen wounded. Afterwards, the Southern Government of China sent several warships to patrol around Macao and made four demands, including: the Portuguese had to make an apology to China and punish the officers who caused the trouble; the Portuguese ships ought not to sail to Yinkang and Wanzai and they had to ban gambling in Macao within a definite time. In Washington, the representatives of the Northern Government of China refused to hold border delimitation talks with the Portuguese representatives on the grounds that no one from the Southern Government was participating in the talks. The Portuguese plan failed once more. Before long, the Portuguese Government again delivered a draft about Macao border problem, this time, to the League of Nations. For all its accustomed partiality to the West, the international organization was also unable to solve this thorny problem. So as long as ten years after the establishment of the Republic of China, the border of Macao was still not delimitated.

On May 29, 1922, the Portuguese troops killed and wounded a large number of Chinese workers and urban inhabitants. After the massacre, both the Southern Government and the Northern Government made stern presentations to the Portuguese side. Many social organizations held meetings and sent telegrams protesting the atrocity of the Portuguese authorities in Macao, asking the government to retrieve Macao at once. Among them, the Guangzhou Citizen Society Backing up Foreign Affairs and other organizations from all walks of life passed a resolution of six points:

From then on, so far as the Chinese people were concerned, the Macao problem was no longer a border problem, but a question of when to retrieve the territory. In November 1924, after Sun Yat-sen sponsored the National Conference and started the national movement to abolish all unequal treaties, the abolition of unequal treaties became the common voice of the people of the whole nation. Even the Ministry of Foreign affairs of the Northern Government formally presented a note to all the countries concerned, including Portugal, asking to revise the unequal treaties. On February 6, 1928, before its complete collapse, the Northern Government of China telegraphed Wang Tingzhang, the Chinese Minister to Portugal, instructing him to announce to the Portuguese government that when the treaty between China and Portugal came up for renewal, the two sides should fix a date to hold talks to replace it with a new one based on the principle of mutual equality and solving the Macao problem. In June of the same year, the Guomintang troops occupied Beijing. On July 10, the Ministry of Foreign Affairs of the Nationalist Government notified the Portuguese Minister to China, Joao Antonio de Bianchi, that the treaty between China and Portugal had expired and become null and void on April 28, 1922. On August 2, Bianchi denied that the treaty had become invalid, but expressed the desire to revise the existing treaty on the basis of mutual respect for each other's territory and sovereignty.

At the beginning of September, 1928, the Assistant Minister of Foreign Affairs, Tang Yueliang, and the Portuguese representative Bianchi began to negotiate a new treaty. The Nationalist Government had already issued its declaration of abolishing all the unequal treaties, so it should no longer recognize Portugal's "perpetual occupation of Macao". The Ministry of Foreign Affairs of the Nationalist Government said that they would like to discuss the retrieval of Macao from Portugal in the spirit of friendship and in accordance with the Nationalist Party's policy of giving favoured treatment to minorities. But the Portuguese government instructed Bianchi that the revision of treaty should take not-involving-Macao as an important principle, or Portugal would prefer a status without a treaty with China. Since the Nationalist Government lacked the determination to retrieve Macao immediately, the Preliminary Treaty of Peking signed on December 19, 1928 had only five articles, and Macao not mentioned. China's retrieval of sovereignty over Macao rather than the border delimitation became the main unsettled issue between China and Macao.

Summing up the whole story of the Macao border delimitation talks, we can see many reasons for the repeated failure of border talks: 1. Some Portuguese colonialists attempted to expand Macao's occupied area through negotiations. 2. People all over China and overseas Chinese were strongly against offering further concessions to the Portuguese colonialists. 3. The Chinese governments thought it not worthwhile to make more concessions to Portugal, which no longer posed any threat to China. By the middle of 1920s, history had entered a new stage. To the Chinese people and Chinese government, it was no longer necessary to delimitate the border of Macao.