A few days later there came an official intimation that he had received a commission in the cavalry, and had at General Magruder's request been appointed to his staff, and he at once entered upon his new duties.
Fortress Monroe, at the entrance of Hampton Roads, was still in the hands of the Federals, and a large Federal fleet was assembled here, and was only prevented from sailing up the James River by the _Merrimac_, a steamer which the Confederates had plated with railway iron.

They had also constructed batteries upon some high bluffs on each side of the river.

In a short time 5000 negroes were set to work erecting batteries upon the York River at Yorktown and Gloucester Point, and upon a line of works extending from Warwick upon the James River to Ship Point on the York, through a line of wooded and swampy country intersected by streams emptying themselves into one or other of the rivers.
This line was some thirty miles in length, and would require 25,000 men to guard it; but Magruder hoped that there would be sufficient warning of an attack to enable re-enforcements to arrive in time to raise his own command of about 10,000 men to that strength.

The negroes worked cheerfully, for they received a certain amount of pay from the State; but the work was heavy and difficult, and different altogether to that which they were accustomed to perform.

The batteries by the sides of the rivers made fair progress, but the advance of the long line of works across the peninsula was but slow.