DISEASES OF CATTLE 265 



each group of hogs a similar number of untreated hogs were ex- 

 posed as checks. As the cattle and hogs were exposed in the same 

 tuberculosis environment in which the degree of immunity ac- 

 quired by all the other bovo-vaccinated animals discussed in this 

 paper was tested, no checks were really necessary for the Hey- 

 manns treated cattle. The checks on the other experiments were 

 serviceable for this one also, but, nevertheless, 4 additional cattle 

 as special checks 'on the value of the Heymanns method were added 

 to the already large number used to prove the character of the tu- 

 berculous environment to which exposure was made. 



Among the Heymanns treated hogs 1 contracted generalized 

 tuberculosis from the treatment and 1 died prematurely as the re- 

 sult of an injury. When the remaining 8 hogs with their 10 

 checks were killed, after an exposure to natural infection varying 

 from 8 months to a year, all the principals and checks were found 

 to be affected with tuberculosis, not one of either lot having escaped 

 the disease; and the lesions in the treated animals were in no re- 

 spect different from those found in the checks. Hence it is very 

 clear that Heymanns's method is absolutely worthless for hogs. 



Among the 12 cattle treated 1 died prematurely, and the re- 

 maining II, when they were killed and examined post-mortem, 

 all showed lesions of tuberculosis, and the lesions were very similar 

 to the tuberculous lesions found in the 4 cattle that served as spe- 

 cial checks on the Heymanns capsule cattle. One of the treated 

 animals showed tuberculosis directly traceable to the capsule with 

 which it was inoculated for protection. Hence, as with the hogs, 

 the only conclusion that can be drawn with the cattle is that 

 Heymanns's capsule method of bovo-vaccination is inefficient. 



In order to test the claims made by Prof. Heymanns that the 

 vegetable sack in which he incloses the tubercle bacilli used in his 

 method of bovo-vaccination would not permit the passage of bac- 

 teria, a number of sheep were inoculated with anthrax bacilli in- 

 closed in Heymanns's capsules. The sheep rapidly contracted and 

 succumbed to anthrax, and the anthrax bacilli (which are larger, 

 of course, than tubercle bacilli) were proven to have escaped 

 through the walls of the capsules and to have gotten into the blood 

 circulation. Blood examined from the tips of the ears of the sheep 

 showed numerous anthrax bacilli. We may conclude from this 

 that the fact that tubercle bacilli under the skin in Heymanns's 

 capsules are frequently restrained at the point of inoculation de- 

 pends upon other conditions than the inability of the germs to pass 

 through the walls of the vegetable sack in which they are enveloped. 



BLOOD TRANSFUSIONS. 



It may be of interest to add a short note that blood transfu- 

 sions from highly immunized cattle into tuberculous cattle for 

 curative purposes and into healthy cattle in order to make them 

 resistant to tuberculosis have been tested on a small scale. The 

 idea that such transfusions may give good results originated with 

 Dr. George W. Crile, of Cleveland, Ohio, who personally made the 

 various transfusions required in the experiment. 



