Caesar's men daily carried on their works to straiten the enemy; those of Pompey, having the advantage of numbers, did the same to enlarge themselves, and severely galled the enemy by their slingers and archers.16.Caesar, however, was indefatigable; he caused blinds or mantalets to be made of the skins of beasts, to cover his men while at work; he cut off all the water that supplied the enemy's camp, and the forage from the horses, so that there remained no more subsistence for them.17.But Pompey at last resolved to break through his lines, and gain some other part of the country more convenient for encampment.

Accordingly, having informed himself of the condition of Caesar's fortifications from some deserters who came over to him, he ordered the light infantry and archers on board his ships to attack Caesar's entrenchments by sea, where they were least defended.18.

This was done with such effect, that though Caesar and his officers used their utmost endeavours to hinder Pompey's designs, yet by means of reiterated attempts, he at last effected his purpose of extricating his army from its present camp, and of encamping in another place by the sea, where he had the convenience both of forage and shipping.
19.

Caesar being thus frustrated in his views of blocking up the enemy, and perceiving the loss he had sustained, resolved at last to force Pompey to a battle, though upon disadvantageous terms.20.

The engagement began by attempting to cut off a legion which was posted in a wood; and this brought on a general battle.