His army, four hundred thousand strong, defiled from the gates of Samarcand, and marching to the north, between the Aral and the Caspian Seas, traversed vast plains, where thousands of wild cattle had long enjoyed undisturbed pasturage. These cattle afforded them abundant food. The chase, in which they engaged on a magnificent scale, offered a very brilliant spectacle. Thousands of horsemen spread out in an immense circle, making the tent of the emperor the central point. With trumpet blasts, the clash of arms and clouds of javelins and arrows, the cattle and wild beasts of every kind were driven in upon the imperial tent, where Tamerlane and his lords amused themselves with their destruction. The soldiers gathered around the food thus abundantly supplied, innumerable fires were built, and feasting and mirth closed the day. Vast herds of cattle were driven along for the ordinary supply of the troops, affording all the nourishment which those rude barbarians required. Pressing forward, in a long march, which occupied several months, Tamerlane crossed the Volga, and entered the south-eastern principalities of Russia. The tidings of the invasion spread rapidly, and all Russia was paralyzed with terror. The grand prince, Vassali, however, strove with all his energies to rouse the Russians to resistance. An army was speedily collected, and veteran leaders placed in command. The Russian troops were rapidly concentrated near Kolomna, on the banks of the Oka, to dispute the passage of the river. All the churches of Moscow and of Russia were thronged with the terrified inhabitants imploring divine aid, the clergy conducting the devotions by day and by night. Tamerlane, crossing from the Volga to the Don, ascended the valley of the latter stream, spreading the most cruel devastation everywhere around him. It was his design to confound his enemies with terror. He was pressing on resistlessly towards Moscow, and had arrived within a few days' march of the Russian army on the banks of the Oka, when suddenly he stopped, and remained fifteen days without moving from his encampment. Then, for some cause, which history has never satisfactory explained, he turned, retraced his steps, and his banners soon disappeared beyond the frontiers of the empire. It was early in September when he commenced this retrograde march. Some have surmised that he feared the Russians, strongly posted on the banks of the Oka, others that he dreaded the approaching Russian winter; others that intelligence of some conspiracy in his distant realms arrested his steps, and others that God, in answer to prayer, directly interposed, and rescued Russia from ruin. The joy of the Russians was almost delirious; and no one thought even of pursuing a foe, who without arriving within sight of the banners of the grand prince, or without hearing the sound of his war trumpets, had fled as in a panic.