520 
E. A. V. SCHWEINITZ. 
temperature dropped to 101.3 0 , aud she rested the foot on the 
floor better than she had done since she was admitted. Im¬ 
provement was steady from this time till she was discharged 
on February 18th. We alternated keeping her in a sling and 
in a box stall on peat moss. In the box stall she would lie 
down, usually on her lame side, and would have to be turned 
over before she could rise. Opium and other sedatives were 
given as thought best. She was fat when she came in, but on 
February 1st was a mere skeleton ; but after that she began 
to gain flesh quite rapidly. 
Case No. 4.—A black gelding, weighing about 1,300 pounds, 
was admitted to the hospital November 3d, 1888, with a nail 
wound of the near hind foot, half an inch from the point of 
the frog. 
He was treated much the same way as the case just 
recited. He also lost considerable flesh, and for about a week 
could not rise from either side without the aid of slings. The 
discharge of synovia began rather abundantly, and gradually 
dwindled down till December 16th, when it was entirely 
stopped. The horse was discharged December 24th, walking 
fairly well ; was rested in his owner’s stable for about a 
month, when he walked sound and was put to work. 
THE PRODUCTION OF IMMUNITY 
WITH THE CHEMICAL SUBSTANCES FORMED DURING THE 
GROWTH OF THE BACILLUS OF HOG CHOLERA. 
By E. A. y. Sohweinitz, Ph.D., 
Chemical Laboratory, Bureau of Animal Industry, Department of Agriculture, 
Washington, D. C. 
As a continuation of the preliminary paper on the 
ptomaines from the hog cholera germ, presented by us to 
the Chemical Section of the American Association for the 
Advancement of Science, in August, and published in the 
Medical News, September 6, 1890, we present now a some¬ 
what detailed account of the successful experiments in the 
production of immunity in guinea-pigs which have been made 
up to date. The work from this standpoint again is, of course, 
