The Portuguese were willing to be the medium between the Boers and the people of other parts of the earth, but they asked for and received a large percentage of the profits.
When the mines of the Johannesburg gold district were closed down, and the Portuguese heard that they would no longer receive a compulsory contribution of four shillings from every native who crossed the border to work in the mines, the officials felt uneasy on account of the great decrease in the amount of public revenues, but it did not worry them for any great length of time.

They met the situation by imposing a tax of eight shillings upon every one of the thousands of natives who returned from the mines to their homes in Portuguese territory.

About the same time the Uitlanders from the Transvaal reached Lorenzo Marques, and, in order to calm the Portuguese mind, every one of the thousands of men and women who took part in that exodus was compelled to pay a transit tax, ranging from eight shillings to a sovereign, according to the size of the tip tendered to the official.
When the van of the foreign volunteers reached the port there was a new situation to be dealt with, and again the principle of "When in doubt impose a tax" was satisfactorily employed.

Men who had just arrived in steamers, and who had never seen Portuguese territory, were obliged to secure a certificate, indicating that they had not been inhabitants of the local jail during the preceding six months; a certificate from the consular representative of their country, showing that they possessed good characters; another from the Governor-General to show that they did not purpose going into the Transvaal to carry arms; a fourth from the local Transvaal consul to indicate that he held no objections to the traveller's desire to enter the Boer country; and one or two other passports equally weighty in their bearing on the subject were necessary before a person was able to leave the town.

Each one of these certificates was to be secured only upon the payment of a certain number of thousand reis and at an additional expenditure of time and nervous energy, for none of the officials could speak a word of any language except Portuguese, and all the applicants were men of other nationalities and tongues.