barrack. I had designed using the first barrack to the right on entering the outer gate for issuing commissary stores after the hospital and temporary fences are removed. With the above explanations I trust it will meet with your approval. Every effort has been and is now being made with a view to the removal of the troops and the hospital outside of the prison inclosure. The difficulty of obtaining lumber has been a serious one, and it may still delay the removal of the hospitals. The barracks for the Thirty-seventh Iowa Volunteers are just now ready, and they are moving in them. Surgeon Clark suggested that the seven barracks they had been occupying remain fenced off, and that they be used to quarantine, not allowing communication between the newly arrived prisoners and the others until we are satisfied that they are free from contagious diseases. It met my hearty approval and I hope it will meet with your approbation. There is a fair prospect that the new prisoners' hospital will be completed within two weeks from this date. That will clear the thirteen barracks in the prison inclosure that are now used for hospital wards. The cases of variola are decreasing rapidly and the prospects are good for a comparatively healthy camp in a short time.

I am, colonel, very respectfully, your obedient servant,

A. J. JOHNSON,

Colonel Fourth Regiment, Veteran Reserve Corps, Commanding Post.

HEADQUARTERS ROCK ISLAND BARRACKS,
Rock Island, Ill., May 9, 1864.

Colonel WILLIAM HOFFMAN, U. S. Army,

Commissary-General of Prisoners of War, Washington, D. C.:

COLONEL: Your letter of the 21st ultimo was duly received. My letter of the 16th, having the omission of my signature, is herewith returned properly signed. The only estimate of the cost of the rebel hospital of which I have any official knowledge was the one of Captain Reynolds, assistant quartermaster, of the 15th of March, inclosed to you in my letter dated March 21, replying to yours of March 10. That estimate was $24,225. I suppose the estimate of $18,000 was given by Surgeon Clark in his first recommendation of the construction of the hospital. The plans were prepared under his directions and the estimate given was not, probably, given in detail. Such estimates are, of course, inaccurate, and usually too low. When authority was given me to build the hospital I conferred with the contractors who were doing Government work for the assistant quartermaster in reference to letting the work by contract on account of the prison fund. Objection was made by them to undertaking so large a contract and waiting upon the prison fund for payment, as sufficient funds would not accumulate to liquidate so large an indebtedness upon the completion of the work. Subsequently Captain Reynolds consented to take charge of the construction of the work, and immediately commenced the same. The materials were purchased and the carpenters' and other work done under contracts then existing in the quartermaster's department. It was my understanding that Captain Reynolds proposed to put up the buildings and liquidate the indebtedness incurred thereby, and I agreed with him to appropriate $4,000 monthly out of the prison fund until the whole cost of the work was paid. Captain Reynolds had already constructed three addition variola wards, 22 by 150 feet each, and the other outbuildings mentioned in his letter of the 16th of March. There are in all six variola wards. The other three were put up by me and have been paid for out of the prison fund.