Le Fort, however, when he perceived how deep was the interest which Peter felt in the subject, made inquiries, and at length succeeded in finding among the Dutch merchants that were in Moscow the means of procuring some ship-builders to build him several small vessels, which, when they were completed, were launched upon a lake not far from the city. Afterward other vessels were built in the same place, in the form of frigates; and these, when they were launched, were properly equipped and armed, under Le Fort's direction, and the emperor took great interest in sailing about in them on the lake, in learning personally all the evolutions necessary for the management of them, and in performing sham-fights by setting one of them against another. He took command of one of the vessels as captain, and thenceforward assumed that designation as one of his most honorable titles. All this took place when Peter was about twenty-two years old. Not very long after this the emperor had an opportunity to make a commencement in converting his nautical knowledge to actual use by engaging in something like a naval operation against an enemy, in conjunction with several other European powers, he declared war anew against the Turks and Tartars, and the chief object of the first campaign was the capture of the city of Azof, which is situated on the shores of the Sea of Azof, near the mouth of the River Don. Peter not only approached and invested the city by land, but he also took possession of the river leading to it by means of a great number of boats and vessels which he caused to be built along the banks. In this way he cut off all supplies from the city, and pressed it so closely that he would have taken it, it was said, had it not been for the treachery of an officer of artillery, who betrayed to the enemy the principal battery which had been raised against the town just as it was ready to be opened upon the walls. This artilleryman, who was not a native Russian, but one of the foreigners whom the Czar had enlisted in his service, became exasperated at some ill treatment which he received from the Russian nobleman who commanded his corps; so he secretly drove nails into the touchholes of all the guns in the battery, and then, in the night, went over to the Turks and informed them what he had done. Accordingly, very early in the morning the Turks sallied forth and attacked the battery, and the men who were charged with the defense of it, on rushing to the guns, found that they could not be fired. The consequence was that the battery was taken, the men put to flight, and the guns destroyed. This defeat entirely disconcerted the Russian army, and so effectually deranged their plans that they were obliged to raise the siege and withdraw, with the expectation, however, of renewing the attempt in another campaign.