114 TECHNICAL ANALYSIS OF 



investigation involves, the very same liquids should be made 

 use of which are employed in the brewery. Opinions, how- 

 ever, are not yet quite unanimous on this last point, and, 

 especially towards the end of the last decade, a contrary 

 view was expressed by several prominent bacteriologists. 

 At that time a large number of investigations on the micro- 

 organisms contained in water were carried out on all sides 

 by means of Koch's gelatine method, and not only in 

 hygienic, but also in zymotechnic laboratories. In an ex- 

 tensive work on such analyses which was published in 1887 

 by Hueppe, the latter emphasises his opinion that this 

 method is the most important for the solution of practical 

 questions which relate both to technology and to hygiene. 

 He makes no distinction in this respect ; the gelatine should 

 be employed in all cases. 



I could not help at once regarding this as a great mistake ; 

 and after carrying out the necessary experiments in this 

 direction, I replied in a short communication which appeared 

 early in 1888 in the ' Zeitschrift fur das gesammte Brau- 

 wesen.' I thereby attained my object, in that Hueppe and 

 some of the other advocates of the gelatine method changed 

 their opinion on this point, but in the meantime it had 

 become so customary in most zymotechnic laboratories to 

 employ exclusively Koch's hygienic method, that it was 

 very difficult to effect a change in this respect. My paper 

 was read with attention, but, as was to be expected, was not 

 received with favour. Even Hueppe could not suppress his 

 dissatisfaction, although in the main he recognised that I 

 was right. Curiously enough, my work was regarded by 

 most of the German bacteriologists as an attack on Koch's 

 method, which, however, it was not in the least ; its object 

 was merely to warn against the misuse of the latter. 



When, during my visit to London in 1889, I read a paper 

 on this subject before " The Laboratory Club," I was likewise 

 opposed on the same grounds from several sides. In England 



