As soon as they had rested from this hard struggle, Cortes summoned his officers, to consult as to the time and manner of their retreat. Some advised that they should sally out boldly by day, when they could see their enemies, and mark every danger. Others thought it best to make the attempt under cover of the night, thinking to escape unobserved through the darkness, and trusting to a superstition of the Mexicans, which would not allow them to attack an enemy during the hours of repose. An old soldier now came in, and pretending to be an astrologer, urged that the attempt should be made by night. In a little time, it was settled that they should start out at midnight. As the Mexicans had broken down the bridges of the causeways to prevent their escape, Cortes at once caused a portable bridge to be made, strong enough to allow his army and all the baggage to pass the openings. He then commanded all the treasure that had been collected to be brought forward, and separating the fifth part which belonged to the King, left the rest for his men; at the same time advising them not to load themselves with it, as it might prove burdensome in their perilous retreat. He next ordered the plan of march. The van of his army, consisting of two hundred of his best soldiers, together with twenty horsemen, was placed under the command of Sandoval, aided by Diego de Ordaz and Francisco Lugo. The rear, which contained most of the Spanish troops, was intrusted to Pedro de Alvarado and Velasquez de Leon. Cortes himself, aided by Christoval de Olid and Davila, took charge of the centre, in which were placed the children of Montezuma, and other prisoners of distinction, together with the baggage, artillery, and portable bridge. The Tlascalans, Chempoallans, and Cholulans, amounting to several thousands, were scattered among the three divisions. To aid them at the time of their departure, the night set in densely dark, with a thick fog, and heavy falls of rain. At midnight, the van left the quarters, and the other divisions soon followed. In deep silence they moved toward the causeway of Tacuba, because that was known to be the shortest, and least frequented by the Mexicans. They reached the first breach unmolested, and at once commenced fixing their bridge for a passage.