It was now the hour of vespers, and, as night must soon overtake them, he made no further attempt to pursue his advantage. Ordering the trumpets, therefore, to sound a retreat, he drew off his forces in good order, taking with him the artillery which had been abandoned in the square. The allies first went off the ground, followed by the Spanish infantry, while the rear was protected by the horse. The Aztecs hung on the closing files, and, though driven back by frequent charges of the cavalry, still followed in the distance, shooting off their ineffectual missiles, and filling the air with wild cries and howlings, like a herd of ravenous wolves disappointed of their prey. It was late before the army reached its quarters at Xoloc.[18] Cortés had been well supported by Alvarado and Sandoval in this assault on the city; though neither of these commanders had penetrated the suburbs, deterred, perhaps, by the difficulties of the passage, which in Alvarado’s case were greater than those presented to Cortés, from the greater number of breaches with which the dike in his quarter was intersected. Something was owing, too, to the want of brigantines, until Cortés supplied the deficiency by detaching half of his little navy to the support of his officers. Without their co-operation, however, the general himself could not have advanced so far, nor, perhaps, have succeeded at all in setting foot within the city. The success of this assault spread consternation not only among the Mexicans, but their vassals, as they saw that the formidable preparations for defence were to avail little against the white man, who had so soon, in spite of them, forced his way into the very heart of the capital. Several of the neighboring places, in consequence, now showed a willingness to shake off their allegiance, and claimed the protection of the Spaniards. Among these were the territory of Xochimilco, so roughly treated by the invaders, and some tribes of Otomies, a rude but valiant people, who dwelt on the western confines of the Valley.[19] Their support was valuable, not so much from the additional reinforcements which it brought, as from the greater security it gave to the army, whose outposts were perpetually menaced by these warlike barbarians.[20] The most important aid which the Spaniards received at this time was from Tezcuco, whose prince, Ixtlilxochitl, gathered the whole strength of his levies, to the number of fifty thousand, if we are to credit Cortés, and led them in person to the Christian camp. By the general’s orders, they were distributed among the three divisions of the besiegers.[21]