On paper the strength of a Confederate company was 110 men. This number was eroded the day they reported for duty from desertions, absentees for sickness, death from accidents, death from disease, detailed men, etc.

If he was requisitioning straw for 21 men then that was probably his effective strength that he had on hand at the time. By mid-war, it was rare for companies to have more than half of their strength. By the end of the war many regiments were shells of their former selves. For example, the 39th Georgia reported a strength of 114 present, with 84 total effective on April 8, 1865. At full strength a regiment would be 49 officers and 1,340 men.

By doctrine (Hardee's Rifle and Light Infantry Tactics, for the Instruciton, Exercise and Manoeuvres of Riflemen and Light Infantry), a company did have two platoons but it was never seen evidence that they were maneuvered as such. Once a company is depleted to such an extent it would be impractical to attempt to manuever 21 men in multiple elements. You would loose what little massed firepower you would already have.

Please let me know if you have any questions.

Respectfully,

Gerald D. Hodge, Jr.
M.A. Military History - Civil War Concentration.
War Between the States Historian
Historian: 39th Georgia Volunteer Infantry Regiment