PROTECTIVE INOCULATIONS. 321 



The experiments were for the most part made by Professor Schin- 

 delka, of Vienna. The tests were made with doses ranging from 0.1 

 gramme to 0.2 gramme. The number of horses treated, for diagnos- 

 tic purposes, was four hundred and fifty-five; of these one hundred 

 and forty-seven were examined post mortem. In general the infected 

 horses reacted and the others did not. A reaction of 2 C C. and up- 

 ward, running a typical course, was evidence that the animal was in- 

 fected, and such animals were killed and carefully examined by au- 

 topsy. 



A reaction of 1.3 to 1.9 C., running a typical course, was taken 

 as evidence that the animal was probably infected, and called for its 

 isolation and a subsequent inoculation after an interval of four weeks. 



A reaction of less than 1.2 C., or an atypical course of the febrile 

 reaction, was taken as evidence of non-infection. 



The typical febrile reaction consisted in a rapid or gradual eleva- 

 tion, according to the dose, then a fall of some tenths of a degree, a 

 subsequent elevation to the highest previously reached point or above, 

 and a gradual fall to the normal. The atypical reaction, which some- 

 times occurs in healthy animals, consists in an early and rapid eleva- 

 tion followed by an equally rapid fall to the normal. To properly 

 distinguish the typical temperature curve, upon which the diagnosis 

 depends, hourly observations are considered necessary. 



Schiitz (1894), as a result of his experiments on fifty-four horses, 

 arrives at the conclusion that malleiu may give rise to the so-called 

 " typical reaction " in horses which are not infected with glanders. 



Hutyra and Preiz (1894), as a result of their extended researches, 

 arrive at the conclusion that the use of malleiu constitutes the most 

 important means for the early diagnosis of glanders in horses. They 

 conclude that a temperature of 39.4 C. may be accepted as a safe 

 positive mallein reaction. According to them the reaction commences 

 from four to six hours after the injection, and reaches its maximum 

 in from eight to fourteen hours rarely in sixteen to twenty hours. 

 The return to the normal occurs in from twenty -four to thirty-six 

 hours. The authors last named give the following directions for the 

 preparation of mallein : The virulence of the glanders bacillus is first 

 increased by passing it through a series of guinea-pigs. Cultures 

 are then made upon sterilized potato. When the culture and potato 

 have become quite dry and dark colored they are collected in a glass 

 dish and covered with a liquid consisting of equal parts of glycerin 

 and distilled water, containing three to five parts per thousand of 

 mercuric chloride. After standing for from ten to fourteen days in 

 an incubating oven at 37.5 C., the liquid. is filtered through paper 

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