The suggestion accorded well with Yermak's humor. He at once began to enlist volunteers for the enterprise, adding to his own Cossack band a reinforcement of Russians and Tartars and of German and Polish prisoners of war, until he had sixteen hundred and thirty-six men under his command. With these he crossed the mountains in 1580, and terrified the natives to submission with his fire-arms, a form of weapon new to them. Making their way down the Tura and Taghil Rivers, the adventurers crossed the immense untrodden forests of Tobol, and Kutchum, the Tartar khan, was assailed in his capital town of Ister, near where Tobolsk now stands. Many battles with the Tartars were fought, Ister was taken, the khan fled to the steppes, and his cousin was made prisoner by the adventurers. Yermak now, having added by his valor a great domain to the Russian empire, purchased the favor of Ivan IV. by the present of this new kingdom. He made his way to the Irtish and Obi, opened trade with the rich khanate of Bokhara, south of the desert, and in various ways sought to consolidate the conquest he had made. But misfortune came to the conqueror. One day, being surprised by the Tartars when unprepared, he leaped into the Irtish in full armor and tried to swim its rapid current. The armor he wore had been sent him by the czar, and had served him well in war. It proved too heavy for his powers of swimming, bore him beneath the hungry waters, and brought the career of the victorious brigand to an end. After his death his dismayed followers fled from Siberia, yielding it to Tartar hands again. Yermak--in his way a rival of Cortez and Pizarro--gained by his conquest the highest fame among the Russian people. They exalted him to the level of a hero, and their church has raised him to the rank of a saint, at whose tomb miracles are performed. As regards the Russian saints, it may here be remarked that they have been constructed, as a rule, from very unsanctified timber, as may be seen from the examples we have heretofore given. Not only the people and the priests but the poets have paid their tribute to Yermak's fame, epic poems having been written about his exploits and his deeds made familiar in popular song. Though the Cossacks withdrew after Yermak's death, others soon succeeded them. The furs of Siberia formed a rich prize whose allurement could not be ignored, and new bands of hunters and adventurers poured into the country, sustained by regular troops from Moscow. The advance was made through the northern districts to avoid the denser populations of the south. New detachments of troops were sent, who built forts and settled laborers around them, with the duty of supplying the garrisons with food, powder, and arms. By 1650 the Amur was reached and followed to the Pacific Ocean.