Thank you, Frederick. I appreciate your help. I checked the Confederate Service Record for Lieutenant Colonel John H. Richardson and found two items of interest.

Adjutant and Inspector General’s Office
Richmond, March 29, 1862
Special Order No. 72
Lieutenant Colonel J. H. Richardson, Commanding 46th Regiment Virginia Volunteers will proceed to Yorktown with the following companies and report for duty with Major General Magruder.
Company A, B, C, E, H,
Company I, 59th Regiment Virginia Volunteers.
By command of the Secretary of War
Jno Withers
Assistant Adjutant General

I also found a ration request for the month of April 1862 that identified the unit strength.
Abstract of provisions issued from April 4, 1862 to April 30, 1862.
April 4 to April 10 – 364 men
April 11 to April 17 – 386 men
April 18 to April 22 – 389 men
April 23 to April 30 – 396 men
Station “is in the field”.
It includes a list of rations broken down by type and quantities.