440 SCIENCE PROGRESS. 



an extract of bacillus mallei as a means for conferring im- 

 munity, and he noticed that a definite rise in body tempera- 

 ture and local swelling followed a subcutaneous injection. 

 In the succeeding year he more particularly indicated its 

 value as a means of diagnosis. Both these Russian 

 observers worked independently with the aim of rendering 

 animals immune to glanders, and published their results 

 before Koch made his communication on tuberculin, but 

 this gave an enormous impulse to the study of mallein and 

 various solid and fluid preparations of this substance have 

 now been obtained. Pearson (5), Preusse (6) who followed 

 Koch's procedure for tuberculin, Johne (7), Gutzeit (8), 

 Preisz (9), Bonome and Vivaldi (10), Malzew (11), 

 Macfadyean (12), Roux (13), Foth (14) and Kresling (15) 

 among others have prepared mallein, though at the present 

 time in FYance, Russia and Germany, mallein of Roux, 

 Preusse and Foth is chiefly used. Two of these are 

 liquids and the last is a powder with a faint yellow tint. 

 Mallein like tuberculin obviously must consist of 

 soluble bodies derived from the microbe itself and from the 

 products of bacterial activity as well as substances in the 

 original culture media, and repeated attempts have been 

 made to isolate a specific body from this complex material. 

 Dialysis of fluid mallein shows that both the substances 

 which remain and those which pass through the membrane 

 are physiologically active, and an alcoholic precipitate of 

 mallein acts precisely like the original material (15). A 

 chemically pure mallein has not yet been seen, and attempts 

 to obtain such a body from proteid-free nutrient media have 

 hitherto been failures (16). Mallein undoubtedly contains 

 nitrogenous bodies some of which belong to the proteid 

 group, such as the bacterial proteines and albumoses which 

 are possibly identical, or as Buchner points out the proteines 

 contain albumoses. Both these substances are capable of 

 exciting fever when injected into animals, and numerous 

 bacteria besides bacillus mallei can produce them. If 

 albumoses are separated from a filtrate, injection of these 

 produces less febrile disturbances than the original filtrate 

 (17). Matthes has recently attempted to decide the ques- 



