EXPERIMENT STATION BULLETINS. 519 



or less. In very advanced cases a large amount is indicated in the 

 judgment of experienced operators. Koch ascertained that one milligram 

 or less of tuberculin was sufficient to produce a rise of temperature in a 

 man suffering from tuberculosis while it produced no effect in a sound 

 man. The Bureau tuberculin is given in doses of 2 c. c. to full grown cat- 

 tle. This tuberculin, however, is sent out by the Bureau in a diluted form. 

 One-tenth, two-tenths, or three-tenths cubic centimeters of the concen- 

 trated tuberculin is considered sufficient for a single animal. This con- 

 centrated form may be procured from commercial houses, but it is always 

 better to dilute it with an one-half per cent, solution of carbolic acid to 

 make a wholesome dose and one which may readily be handled with a 

 certain degree of security. 



DISINFECTION OF THE PART INJECTED. 



The place selected on the animal for injection should be properly dis- 

 infected with a five per cent, solution of carbolic acid or a solution of cor- 

 rosive sublimate (one part of corrosive sublimate to one thousand parts of 

 water). The spot should be thoroughly washed with either of these solu- 

 tions. This is to prevent infection while injecting. The syringes and 

 needles should be kept sterile and free from contamination. 



THE DIAGNOSTIC VALUE OF TUBERCULIN. 



What value tuberculin possesses as a diagnostic agent could be readily 

 stated, if we should confine our thoughts to our own experience. Ours 

 is, however, the experience of only one and there are many others who do 

 not think exactly as we do. For a man to satisfy himself with his own 

 cooped up experience and then scatter it broadcast as the only correct 

 experience is belittling and obnoxiously unfair. Experimental work with- 

 out a large amount of comparative study means little and does much 

 harm. While I shall give what evidence I possess before completing this 

 bulletin, I should feel that a larger part had been omitted did I not 

 present some experiments and opinions of a few other workers based upon 

 their own experience. 



Soon after Koch announced the discovery of his tuberculin and when 

 scores of investigators were endeavoring to ascertain its physiologic 

 action, Gutman of Dorfat made use of it December 25, 1890, upon some cat- 

 tle. The rectal temperatures were taken at noon of the day of the injec- 

 tion and found to be 28.1° C, 38.5° C and 39° C. After the injection the 

 maximum temperature reached 40° C, 40.8° C and 41.3° C respectively. 

 The fever lasted four, nine and twelve hours. Sticker at about the same 

 period reached almost identical conclusions as Gutman. The former did 

 his work in Kussia and the latter at Cologne, Prussia. Simultaneously 

 with these two workers, at a French veterinary school, experiments of 

 the same nature were in progress. The conclusions were practically the 

 same, that is, tuberculin produced a rise of temperature in tuberculous 

 animals. 



In 1891 Eber summed up results with tuberculin. He showed that of 

 one hundred thirty-four cattle which reacted to tuberculin and autopsied. 

 eighty-five and eighty-three one-hundredths per cent, were tuberculous. 



