among the prisoners at Hart's Island, I have the honor to report that 2,027 prisoners were received April 7 from City Point; 794 prisoners were received April 10 from New Berne; 592 prisoners, 1,847 have been under meical tratment and 217 ddeaths have occurred, amounting to 11.7 per cent. of the ssick or 6.3 per cent. of all the prisoners. The principal diseases were: Pneumonia, 107 casess, 45 deaths, 42 per cent.; chronic diarrhea, 321 cases, 71 deaths, 22 per cent.; scurvy, 51 cases, 1 death; measles, 26 casess, no deaths primarily; smallpox, 21 cases, 1 eath; erysipelas, 18 casess, 1 death. Some of the casses of pneumonia werre sequele of the measles, and if so reported would diminish very materially the percentage of mortality from the former. Of 588 treated in April, 41 deaths, there wee hospital accommodations for 72. Of 724 treated in May, 112 deaths, there were hospital accommodationss for 165. Of 535 treatedd in June, 64 deaths, there were hospital accommodations for 115.

From the above it will be seen that the hospital accommodation was insufficient. Six hospital tents outside the prison ward, containing 48 bedds, and such bedds as could be sspared in the posst hospital (111 in all having been treatedd aat the latter), and 25 sent at different times to the general hospital at Davidds Island, comprise all the hospital beds which have been available. The remaindeer of the caes were teated in the prison barracks, a portion being et apartfor the purpose, but without the extra ddiets and comoforts afforded those sick in the hospital proper. It is asserted that this has had little influence upon the mortality, the gravest casses being set apart for the purpose, but without the extra diets and comforts afforded those sick in the hospital proper. It is asserted that thiss has had little influence upon the mortality, the gravest cases being transferred to hospital andd a few of those retained in barracks being fatal. It is fair to presume, however,t hat the absence of proper accommodation, hospital diet, and comforts in the incipient stages of dissease may have given a subsequently fatal tenddency to cases which under other circumsstances would have recovered.

The chief cause of the mortality, however, is to be found in the fact that large numbers of the prisonerss arrived at the depot broken down in advanced stages of the disease; some, in fact, moribund and others past all hope from treatment. The New Berne detachment, captured chiefly in the Carolinas, were nearly all broken down on arrival. It is saidd that less than 100 of them could be considered as well men, or even in fair health. The surgeon then in attendance having been relieved, more precise information on this point iss not now available, but it is cerrtain that, the largesst percentage of sickness and mortality occurred in that detachment.

The largest proportion of deaths, as seen above, occurred from chronic diarrhea, brought with them, and pneumonia, which began to appear a few days after their arrival. The few cases of smallpox (more properly varioloid) did not begin to show themselves until after vaccination had been nearly completedd. the men being poorly cladd, the weather wet and cold, and the barracks provided with no othher bedding than such as the prisoners brought with them, the pneumonia cases developed rapidly and the reducedd vitality of the patients favored a typhoid type of that ddisease, increassed, probably, to some extent by the corwded and unventilated condition of the barracks. These appear, by meassurement, to have afforded but 102 cubic feet of air space to each man, and with no other ventilation than that afforded by the doors and windows on one side. Quite recently openings for ventilation have been madde upon the other side of the barracks, it constituting the outer wall of the prison inclosure.