In forming his arrangements for going into England, the first thing was, to obtain all the information which was accessible in Gaul in respect to the country.  There were, in those days, great numbers of traveling merchants, who went from one nation to another to purchase and sell, taking with them such goods as were most easy of transportation.  These merchants, of course, were generally possessed of a great deal of information in respect to the countries which they had visited, and Caesar called together as many of them as he could find, when he had reached the northern shores of France, to inquire about the modes of crossing the Channel, the harbors on the English side, the geographical conformation of the country, and the military resources of the people.  He found, however, that the merchants could give him very little information.  They knew that Britain was an island, but they did not know its extent or its boundaries; and they could tell him very little of the character or customs of the people.  They said that they had only been accustomed to land upon the southern shore, and to transact all their business there, without penetrating at all into the interior of the country.

[Sidenote:  Volusenus.]

Caesar then, who, though undaunted and bold in emergencies requiring prompt and decisive action, was extremely cautious and wary at all other times, fitted up a single ship, and, putting one of his officers on board with a proper crew, directed him to cross the Channel to the English coast, and then to cruise along the land for some miles in each direction, to observe where were the best harbors and places for landing, and to examine generally the appearance of the shore.  This vessel was a galley, manned with numerous oarsmen, well selected and strong, so that it could retreat with great speed from any sudden appearance of danger The name of the officer who had the command of it was Volusenus.  Volusenus set sail, the army watching his vessel with great interest as it moved slowly away from the shore.  He was gone five days, and then returned, bringing Caesar an account of his discoveries.

[Sidenote:  Caesar collects vessels.]

In the mean time, Caesar had collected a large number of sailing vessels from the whole line of the French shore, by means of which he proposed to transport his army across the Channel.  He had two legions to take into Britain, the remainder of his forces having been stationed as garrisons in various parts of Gaul.  It was necessary, too, to leave a considerable force at his post of debarkation, in order to secure a safe retreat in case of any disaster on the British side.  The number of transport ships provided for the foot soldiers which were to be taken over was eighty.  There were, besides these, eighteen more, which were appointed to convey a squadron of horse.  This cavalry force was to embark at a separate port, about eighty miles distant from the one from which the infantry were to sail.