WILLIAMSTOWN, MASS., August 10, 1864.

Colonel W. HOFFMAN, U. S. Army,

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

COLONEL: Immediately upon the arrival at New York of the fifty officers recently exchanged at Charleston, S. C., a communication was addressed to the Adjutant-General of the Army, by the senior officer, Brigadier General H. W. Wessells, suggesting that a commission be appointed to visit our prisons, ascertain exactly how Confederate officers and men are treated, and to draw up a code of rules, founded strictly upon their personal experience while prisoners of war, for the government of those Confederates while in U. S. custody.

The subject of treatment of such prisoners has, of course, often and fully presented itself for your consideration, but to us who have practically and personally experienced the attentions of Southern jailers, the subject is one of bitter remembrance, only to be referred to with vindictive and retaliatory spirit.

The Southern authorities claim that they give to prisoners precisely what their soldiers are allowed in the field. It is probably true of the ration, but of nothing else. The Southern soldier, even in his most prosperous days, lived simply upon the handful of corn and bit of bacon upon which he now is supported. Few Northern men, except in an almshouse - and I know of none that ever did so scantily - were ever reduced to the common rule of diet of the Southern race. But beyond their ration the prisoner enjoys none of those essentials to cleanliness, and consequently to health, that are so strictly indispensable. Fresh air, water in abundance for washing and bathing, and opportunity for exercise have been rigidly ignored or forbidden. The most gross lack of administration has characterized their prisons. But, as already referred to, air and water have, although the cheapest luxuries in the Confederacy, been studiously refused, and this more particularly at Andersonville and at Macon, the most recently established of the depots for our captured soldiers. Why should not rebel prisoners be treated exactly like our own? We construct elegant accommodations, spacious, with every convenience, and admit all kinds of luxuries, while our people rot with dirt and scurvy. at Andersonville the scene would disgrace a race of cannibal barbarians. Scores die daily from sheer neglect, and with as little care; less than a rotten sheep would meet at the hands of a brutal owner.

My firm conviction is that the Southern authorities believe we do not dare to give like treatment to their captured. It would perhaps disgrace us to so retaliate. We constantly declared that such rules of treatment as were imposed upon us we should endeavor to have applied to themselves.

At Charleston a vigorous protest, signed by the five general officers (prisoners), procured an immediate change in food, which, I am happy to add, will doubtless be extended to all future prisoners in Charleston. Copies of this letter, and of other correspondence with Confederate authorities upon like points, are now being made to be forwarded to you.

The Southern authorities are exceedingly desirous of immediate exchange of all prisoners. General Wessells and myself had an interview with General Ripley at Charleston on this point. Their urgency is unbounded, but we asserted that it was the poorest possible policy for our Government to deliver to theirs, betted fed and clothed than ever before in their lives and perfectly equipped for the field by Northern generosity, while the United States received in return