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.
The Surgeon General of the Confederate States of America furnished me with the following letter of introduction to the Surgeon in charge of the Confederate States Military Prison at Andersonville, Ga.: CONFEDERATE STATES OF AMERICA, SURGEON GENERAL'S OFFICE, RICHMOND, VA., August 6, 1864.
SIR:--The field of pathological investigations afforded by the large collection of Federal prisoners in Georgia, is of great extant and importance, and it is believed that results of value to the profession may be obtained by careful investigation of the effects of disease upon the large body of men subjected to a decided change of climate and those circumstances peculiar to prison life.

The Surgeon in charge of the hospital for Federal prisoners, together with his assistants, will afford every facility to Surgeon Joseph Jones, in the prosecution of the labors ordered by the Surgeon General.

Efficient assistance must be rendered Surgeon Jones by the medical officers, not only in his examinations into the causes and symptoms of the various diseases, but especially in the arduous labors of post mortem examinations.
The medical officers will assist in the performance of such post-mortems as Surgeon Jones may indicate, in order that this great field for pathological investigation may be explored for the benefit of the Medical Department of the Confederate Army.
S.P.MOORE, Surgeon General.
Surgeon ISAIAH H.WHITE, In charge of Hospital for Federal prisoners, Andersonville, Ga.
In compliance with this letter of the Surgeon General, Isaiah H.White, Chief Surgeon of the post, and R.R.Stevenson, Surgeon in charge of the Prison Hospital, afforded the necessary facilities for the prosecution of my investigations among the sick outside of the Stockade.

After the completion of my labors in the military prison hospital, the following communication was addressed to Brigadier General John H.Winder, in consequence of the refusal on the part of the commandant of the interior of the Confederate States Military Prison to admit me within the Stockade upon the order of the Surgeon General: CAMP SUMTER, ANDERSONVILLE GA., September 16, 1864.
GENERAL:--I respectfully request the commandant of the post of Andersonville to grant me permission and to furnish the necessary pass to visit the sick and medical officers within the Stockade of the Confederate States Prison.

I desire to institute certain inquiries ordered by the Surgeon General.