In those times the expense of keeping elephants was enormous, and oftentimes the animals suffered greatly. At the siege of Pydua, in Macedonia, the elephants were obliged to eat sawdust; and many died, or, as Diodorus Siculus says, “pined away for want of food.” In the histories of the wars that were waged between the generals of Alexander and Ptolemy, elephants are often mentioned, and were evidently relied upon more than any branch of the service. Diodorus Siculus says, when Perdiccas marched to the Nile, and assaulted the fort called the “Camel’s Wall,” he “boldly led up his army close to the fort, and forthwith the targeteers with their ladders mounted the wall; and those that rode upon elephants threw down the fortifications, and demolished the bulwarks. Whereupon Ptolemy, with those of his own guard about him, to encourage the rest of his officers and friends manfully to behave themselves, catched hold of a sarissa, and mounted the bulwark; and so, being on the higher ground, struck out the eyes of the foremost elephant, and wounded the Indian that sat upon him; and as for those that scaled the walls, he hurled them down, dreadfully cut and wounded, into the river. After his example, Ptolemy’s friends valiantly exerted themselves; and, by killing the Indian that governed the next elephant, the beast became unserviceable.” When Ptolemy and Seleucus attacked Demetrius at Gaza, their first care was to protect their army from the shock of the elephants of their enemy; and for this purpose they prepared “an iron palisado, sharp-pointed with iron, and fastened together with chains.” That this precaution was not taken in vain, the same author shows in the following: “And now, when the fight between the horse had been a long time doubtful, the elephants, forced on by the Indians, made so terrible an onset that it appeared impossible for any force to have stood against them. But when they came up to the palisado, the darters and archers sorely galled both the beasts and their riders; and being still forced on, and whipt by the Indians, some of them stuck upon the sharp points of the palisado, with which, besides the multitude of the darts and arrows that galled them, they were in such pain and torment that they caused a horrible tumult and confusion: for these creatures, in plain and level places, bear down all before them; but in those which are rough and craggy, they are of no use or service, because of the tenderness of their feet. Ptolemy, therefore, wisely foreseeing of what advantage this palisado would be, by that means frustrated the rage and fury of the beasts. At length, most of the Indians that rode them being killed, all the elephants were taken, upon which the greatest part of Demetrius’s horse were in such a consternation that they forthwith fled.”