2 



DR. BASTIAIf ON THE 



have found to be highly favourable to the development of fermen- 

 tation in boiled fluids ; secondly, to record fresh instances of the 

 occurrence of fermentation in boiled acid fluids ; thirdly, to bring 

 forward certain crucial evidence bearing upon the disputed inter- 

 pretation of the fertility of boiled neutral or faintly alkaline fluids ; 

 and fourthly, to record fresh instances of the fermentation of 

 guarded neutral fluids after they have been heated to 110° C. and 

 upwards. 



The investigations recorded in the present communication have 

 been made principally with boiled urine, which will, when securely 

 guarded and kept at a temperature of 77°-86° F. (25°-30° C), 

 remain free from all signs of turbidity from the appearance of 

 organisms, as Pasteur, Lister, Roberts, Tyndall, and others have 

 ascertained. The i^«timony of previous investigators on this sub- 

 ject is unnniuioufc. 



M. Pasteur, speaking of sweetened yeast-water and of urine, 

 says* ; — " Nous avona reconnu que ces liquides, portes a la tem- 

 perature de re]>iillii;ion a 100° pendant deux ou trois minutes, 

 puis exposc^s au contact de I'air qui a subi la temperature rouge 

 n'^prouvent aucune alteration." The latter of these fluids may 

 remain, he says, indefinitely, " sans eprouver d'autre alteration 

 qu'une oxydation lente de la matiere albumineuse," and this even 

 *' a la temperature de 25° a 30°, temperature si favorable a la 

 putrefaction de 1' urine." 



Prof. Listerf calls forcible attention to experiments with boiled 

 urine in support of the germ theory, its continued barrenness, 

 when protected after boiling, being the invariable result in his 

 hands. In regard to any organisms and their germs which it 

 might contain, he says : — " It is necessary to maintain the elevated 

 temperature (212° P.) for about five minutes to ensure complete 

 destruction of their vitality." 



Dr. William EobertsJ mentions healthy and diabetic urine as 

 being amongst the easiest fluids to sterilize, " three or four minutes' 

 boiling " sufiicing, as he says, to bring about this result and cause 

 the liquid to remain permanently barren when kept at tempera- 

 tures ranging between 60° and 90° F. 



Prof. Tyndall§ also, in 1875, found five minutes' boiling invari- 



* Ann. de Chimie et de Phys. 1862, t. Ixiv. pp. 58 et 52. 

 t Introductory Lecture delivered in the University of Edinburgh, 1869, p. 19. 

 \ Phil. Trans, vol. clxiv. pt. 2, p. 461. 

 § Phil. Trans. 1876, vol. clxvi. pt. 1, p. 42. 



