320 THE FLOATING-MATTER OF THE AIR. 



in others graceful loops, or becoming coiled into knots 

 of a complexity not to be unravelled. We finally see 

 those filaments resolving themselves into innumerable 

 spores, each with death potentially housed within it, 

 yet not to be distinguished microscopically from the 

 harmless germs of Bacillus subtUis. The bacterium 

 of splenic fever is called Bacillus Anthracis. This 

 formidable organism was shown to me by M. Pasteur 

 in Paris last July. His recent investigations regarding 

 the part it plajs pathologically certainly rank amongst 

 the most remarkable labours of that remarkable man. 

 Observer after observer had strayed and fallen in this 

 land of pitfalls, a multitude of opposing conclusions 

 and mutually destructive theories being the result. In 

 association with a younger physiological colleague, M. 

 Joubert, Pasteur struck in amidst the chaos, and soon 

 reduced it to harmony. They proved, among other 

 things, that in cases where previous observers in Frauce 

 had supposed themselves to be dealing solely with 

 splenic fever, another equally virulent factor was simul- 

 taneously active. Splenic fever was often overmastered 

 by septicaemia, and results due solely to the latter had 

 been frequently made tlie ground of pathological in- 

 ferences regarding the character and cause of the 

 former. Combining duly the two factors, all the 

 previous irregularities disappeared, every result obtained 

 receiving the fullest explanation. On studying the 

 account of this masterly investigation, the words where- 

 with Pasteur himself feelingly alludes to the difficulties 

 and dangers of the experimenter's art came home to 

 me with especial force : ' J'ai tant de fois eprouve que 

 dans cet art difficile de I'experimentation les plus 

 habiles bronchent a. chaque pas, et que I'interpretation 

 des faits n'est pas moins perilleuse.' ' 



' Comptes-Eendus, Ixxxiii. p. 177. 



