From the National Archives, RG 109, Ch. 6, Vol. 364, "Letters Sent & Received, Medical Director's Office, 1864-65." p. 576
Chimborazo Hos. 20 June '64
Sir
After deducting the Med. Officers who are on temporary duty with the local forces and who are sick, I find that I have to-day (17) seventeen ward surgeons on duty.
These seventeen medl officers are expected to take charge of 2400 patients. Of these 2400 most of them are wounded, and not less than 1100 are of the gravest character of wounds.
Some of my best medl officers are absent. Sugn. Davis and A. Surgeons Chapman, Gordon, Dunkley, & Watson sick, A. Surgeon Shuford who left here for temporary duty with local defense, 12 March last is still absent, and A. Surgeons Hendrick & Eppes, also, with the local troops.
Under the circumstances, I would ask for some efficient help in the medl staff of the Hosl. Cannot continue to perform the labor.
Very Respectfully &c.
J. B. McCaw, Surgn in charge
Surg. Carrington