That his government had learned to appreciate his services is shown by the fact that he was soon afterward placed on a joint commission of the English, French, Russians, and Austrians, to lay down a boundary line between Russia and her neighbors at the southwest. It was only one of many later attempts to define the Balkans. "The newly-ceded territory is in great disorder," writes Gordon. "The inhabitants refuse to obey the Moldaves and own nobody's authority. This is caused, I suspect, by Russian intrigues." Already cracks were beginning to show in the new boundary wall. After three years of steady but interesting work following up the ravages of war, Gordon returned home. It was a rest well earned, and likewise needed, for there were still more strenuous days ahead. Then back he went, in the Spring of 1858, to complete his work in the Caucasus. "I am pretty tired of my post as peacemaker," he writes; "for which I am naturally not well adapted. . . . I am quite in the dark as to how my mission has been fulfilled, but it is really immaterial to me, for I will not accept other work of such an anomalous character." The "other work" that was being stored up for him was of quite different nature. He might have called it "anomalous," but it was to tax and bring out every resource in him. China, that land of distance and mystery, was undergoing a period of upheaval. A usurper had tried to seize the reins of government, and the French and British ships had been attacked. The British sent a force of reprisal, somewhat like that sent against the Boxer rebellion in recent years. This was in 1860; and Gordon was sent out with the rank of captain. The first work of this expeditionary force was scarcely worthy of a civilized country. They set fire to a summer palace and gardens of a prince who had mistreated some English prisoners. It was a piece of vandalism that went against the grain with Gordon. "You can scarcely imagine the beauty and magnificence of the palaces we burnt," he writes. "It made one's heart sore to destroy them. It was wretchedly demoralizing work." In the Spring of 1862, Gordon had become a major, and was ordered, with a Lieutenant Carden, to explore the Great Wall of China. This was more to his liking. The two men were congenial and well fitted by temperament and experience for the task. They penetrated provinces in the interior never before entered by a white man, and had a variety of adventures, some amusing, others exciting. During the winter it grew extremely cold, high up in the mountains. He relates that eggs were frozen as hard as if they had been boiled. At another time they are caught in a terrific dust storm, which he thus describes: