Ans. For the purpose of prosecuting investigations ordered by the Surgeon General. Ques. You went there in obedience to a letter of instructions? Ans. In obedience to orders which I received. Ques. Did you reduce the results of your investigations to the shape of a report? Ans. I was engaged at that work when General Johnston surrendered his army. (_A document being handed to witness._) Ques. Have you examined this extract from your report and compared it with the original? Ans. Yes sir, I have. Ques. Is it accurate? Ans. So far as my examination extended, it is accurate. The document just examined by witness was offered in evidence, and is as follows: _Observations upon the diseases of the Federal prisoners, confined in Camp Sumter, Andersonville, in Sumter county, Georgia, instituted with a view to illustrate chiefly the origin and causes of hospital gangrene, the relations of continued and malarial fevers, and the pathology of camp diarrhea and dysentery, by Joseph Jones Surgeon P. A. C. S. Professor of Medical Chemistry in the Medical College of Georgia, at Augusta, Georgia._ Hearing of the unusual mortality among the Federal prisoners confined at Andersonville, Georgia, in the month of August, 1864, during a visit to Richmond, Va., I expressed to the Surgeon General, S. P. Moore, Confederate States of America, a desire to visit Camp Sumter, with the design of instituting a series of inquiries upon the nature and causes of the prevailing diseases. Small pox had appeared among the prisoners, and I believed that this would prove an admirable field for the establishment of its characteristic lesions. The condition of Peyer’s glands in this disease was considered as worthy of minute investigation. It was believed that a large body of men from the northern portion of the United States, suddenly transported to a warm Southern climate, and confined upon a small portion of land, would furnish an excellent field for the investigation of the relations of typhus, typhoid and malarial fevers.” Then follows a letter of introduction to the Surgeon in charge at Andersonville, and a letter to Gen. Winder asking permission to visit the Inner Prison, and an order of Winder granting permission. The report then proceeds. “_Description of the Confederate States Military Prison Hospital at Andersonville, Number of prisoners, physical condition, food, clothing, habits, moral condition, diseases._