510 EXPERIMENT STATION RECORD. 



into the milk was frequently observed in eases where no visible alteration of the 



udder was present. 



The author also demonstrated by experiments that the virulence of human tuber- 

 cle bacilli could be greatly increased by a single passage through goats. In another 

 experiment one goat was inoculated intravenously with t \, g. of a culture of avian 

 tubercle bacilli. This goat was killed after a period of 5 months, at which time the 

 tracheal glands were found to be enlarged, and caseous and tubercle bacilli were also 

 found on the diaphragm and surface of the spleen. 



Experiments -with tuberculins made from human and bovine tubercle 

 bacilli, S. B. Wolbach and H. C. Ernst {Jour. Med. Research, 12 i 1904), ZVb. 3, pp. 

 295-311). — The purpose of experiments reported in this article was to repeat the 

 experiments of Koch with tuberculin <>n tuberculous. guinea pigs, and to test the 

 possibility of specific differences in tuberculins from human and bovine sources. 



Cultures of tubercle bacilli were obtained directly from cases of the disease in 

 man and cattle and were maintained on human and bovine blood. The virulences 

 of the cultures were determined by the method of Theobald Smith, and the strength 

 of the tuberculins by the method of Donitz. < l-uinea pigs were inoculated with this 

 substance and subsequently treated with tuberculins. The detailed results of the 

 experiments are reported in a tabular form. The local effect of tuberculin upon the 

 abscess at the point of inoculation was the most marked action noted as a result of 

 treatment with tuberculin. The abscess increased in size much more rapidly in the 

 control animals, while in treated guinea pigs the abscess generally decreased in 

 size and in a few cases healed. Autopsies made on the guinea pigs used in the 

 experiments failed to siiow any differences in the character of the disease produced 

 by human and bovine tubercle bacilli. 



The authors conclude, therefore, that there is no specific difference between tuber- 

 culins from human and bovine sources, and that the tuberculin treatment acts some- 

 what favorably upon the development of tuberculosis in guinea pigs. 



The channels of infection in tuberculosis in childhood, L. Kingsford (Lan- 

 cet [London], 1904, II, No. 13, pp. 889-892) .—The author presents an analysis of 

 statistics relating to tuberculosis in children during the past 14 years. As a result 

 of a study of these cases the author concludes that about 20 per cent were due to the 

 ingestion of tuberculous material into the alimentary tract. It is stated that perhaps 

 the danger from drinking tuberculous milk has been somewhat exaggerated, but the 

 fact that 20 per cent of the cases of tuberculosis in children appear to arise from 

 primary infection in the alimentary tract makes out a strong case against tuberculous 

 milk. 



Acclimatization to tuberculin, H. Vallee {Ann. Inst. Pasteur, 18 (1904), -ZVo. 9, 

 pp. 545-552).— It has long been supposed that cattle may become nearly immune to 

 the effects of tuberculin as a result of repeated injections. Numerous experiments 

 along this line were carried out and reported by Nocard. The author instituted a 

 series of experiments to test this acquired resisting power to the action of tuberculin. 



It was found that, if the temperature be taken within 2 hours after the second 

 injection of tuberculin and at intervals of 2 hours thereafter for 12 to 14 hours, the 

 temperature curve may show a marked reaction. If, however, the temperature is 

 first taken 12 hours after the injection the reaction may have entirely passed and 

 the experimenter may thus fail to observe it. The author's experiments were 

 carried out on 36 cattle, 32 of which could be definitely declared as tuberculous after 

 the first tuberculin injection. The second tuberculin test was made 48 hours after 

 the first, at which time 28 cattle gave a marked reaction and none of the others 

 could be considered as free from tuberculosis. The temperature curves obtained by 

 the author, however, show that the reaction to the second tuberculin inoculation 

 is of very short duration as compared with that of the first. 



On the basis of these experiments the author concludes that in a majority of cattle 



