In the spring of 1857 Lord Elgin accepted from Lord Palmerston a delicate mission to China at a very critical time when the affair of the lorcha “Arrow” had led to a serious rupture between that country and Great Britain.  According to the British statement of the case, in October, 1856, the Chinese authorities at Canton seized the lorcha although it was registered as a British vessel, tore down the British flag from its masthead, and carried away the crew as prisoners.  On the other hand the Chinese claimed that they had arrested the crew, who were subjects of the emperor, as pirates, that the British ownership had lapsed some time previously, and that there was no flag flying on the vessel at the time of its seizure.  The British representatives in China gave no credence to these explanations but demanded not only a prompt apology but also the fulfilment of “long evaded treaty obligations.”  When these peremptory demands were not at once complied with, the British proceeded in a very summary manner to blow up Chinese forts, and commit other acts of war, although the Chinese only offered a passive resistance to these efforts to bring them to terms of abject submission.  Lord Palmerston’s government was condemned in the House of Commons for the violent measures which had been taken in China, but he refused to submit to a vote made up, as he satirically described it, “of a fortuitous concourse of atoms,” and appealed to the country, which sustained him.  While Lord Elgin was on his way to China, he heard the news of the great mutiny in India, and received a letter from Lord Canning, then governor-general, imploring him to send some assistance from the troops under his direction.  He at once sent “instructions far and wide to turn the transports back and give Canning the benefit of the troops for the moment.”  It is impossible, say his contemporaries, to exaggerate the importance of the aid which he so promptly gave at the most critical time in the Indian situation.  “Tell Lord Elgin,” wrote Sir William Peel, the commander of the famous Naval Brigade at a later time, “that it was the Chinese expedition which relieved Lucknow, relieved Cawnpore, and fought the battle of December 6th.”  But this patriotic decision delayed somewhat the execution of Lord Elgin’s mission to China.  It was nearly four months after he had despatched the first Chinese contingent to the relief of the Indian authorities, that another body of troops arrived in China and he was able to proceed vigorously to execute the objects of his visit to the East.  After a good deal of fighting and bullying, Chinese commissioners were induced in the summer of 1859 to consent to sign the Treaty of Tientsin, which gave permission to the Queen of Great Britain to appoint, if she should see fit, an ambassador who might reside permanently at Pekin, or visit it occasionally according to the pleasure of the British government, guaranteed protection to Protestants and Roman Catholics alike, allowed British subjects to travel to all parts of the empire, under passports signed by British consuls, established favourable conditions for the protection of trade by foreigners, and indemnified the British government for the losses that had been sustained at Canton and for the expenses of the war.