Y ^r W* AttJB 



UFI7BESITT1 



INFECTIOUS DISEASES AtfD MICROBES, ETC. 251 



days' immersion in that medium. As already stated 

 the best temperature for the growth of this bacillus 

 is 37 C. ; at 40 C. its activity is diminished ; and 

 at a temperature ranging from 50 to 60 C. it is 

 killed. Boiling or strongly heating cultivations of 

 all microbes destroys them, or, in other words, the 

 media so treated become sterilised. Goethe knew 

 nothing about microbes, yet, with the genius of a 

 great poet, he makes Mephisto say : 



* Der Luft, dem Wasser, wie der Erden 

 Entwinden tausend Keime sich, 

 Im Trocknen, Feuchten, Warmen, Kalten ! 

 Hatt' ich mir nicht die Flamme vorbehalten, 

 Ich hatte nichts Aparts f iir mich. ' 



In addition to the action of heat, sulphuretted 

 hydrogen, ozone, a solution of salicylic acid, and the 

 electric current (E.M.F. of 2'16 volts), all destroy 

 the vitality of Bacillus tuberculosis. 1 



Although it is out of place to discuss the methods 

 used in the treatment of infectious diseases in a 

 manual devoted to general bacteriology, we give a 

 very brief account of what is known as 'Koch's 

 cure' for tuberculosis. Ever since Dr. Koch dis- 

 covered the tubercle bacillus (in 1882) he has been 

 endeavouring to obtain an inoculating fluid which 

 would kill the bacilli, and bring about a sufficiently 

 strong and healthy reaction to expel them from the 

 body without, at the same time, destroying healthy 

 organs. Such a fluid Koch believes he has dis- 

 covered in his tuberculin, 2 which is a glycerine 



1 See the author's book, loc. cit., pp. 176, 182, 184, and 227. 



2 Deutsche Medizinische Wochenschrift, Nov. 14, 1890, and 

 Jan. 15, 1891. 



