456 Messrs. Harden and Paine. Action of Dissolved [Oct. 17, 



Table XI. — Effect of Partial Desiccation in Vacuo. 



Time. 



Cubic centimetres of carbon dioxide yielded per hour by — 



A. 10 grm. yeast. 

 Control. 



B. 10 grm. yeast 

 dried 2 hours. 



C. 10 grm. yeast 

 dried 4 hours. 



1st hour 

 2nd „' 

 3rd „ 

 4th „ 

 5th „ 

 24 hours (total) 



36 -0 

 15 -3 

 14-1 

 i 12-9 

 13-7 

 281 -6 



46 -1 

 17 -2 

 14-7 

 14-8 

 14-7 

 248-3 



55 -5 

 39 -3 

 38 -7 

 32-4 

 22 -4 

 234 -9 



In this experiment a loss of 3 - 2 grm. of water from 10 grm. of yeast, equal 

 to approximately half the water content of the cells, had the effect of more 

 than doubling the rate of autofermentation. 



(3) The possibility of the removal from the cell of some inhibitory or 

 controlling substance during plasmolysis is negatived by these last experiments, 

 wherein the increase of autofermentation was produced under conditions which 

 render such removal impossible unless the substance be a volatile liquid. 



(4) The disorganisation of the cell, possibly by the disintegration of a 

 material membrane or network, has been adduced as the cause of some of the 

 effects of anaesthetics on the living cell [Overton (7), Lepeschkin (8), Hans 

 Meyer (9)], and it is not impossible that in certain instances this phenomenon 

 plays some part in the acceleration of the autofermentation of yeast. This 

 possibility is specially present in the case of a substance like toluene, which 

 exerts an ansesthetic effect upon yeast. 



The following experiment is typical of many ; 10 grm. yeast were mixed 

 with (a) 25 c.c. water, (h) 25 c.c. water and 5 c.c. toluene, well shaken, and 

 incubated at 25° : — 



Table XII. — Effect of Toluene on the Autofermentation of Yeast. 







Cubic centimetres 



of carbon dioxide. 



Time. 





Water. 



J. "Water + toluene. 





Total. 



Kate per 10 mins. 



Total. 



Kate per 10 mins. 



10 mins. 

 20 „ 

 30 „ 

 40 „ 

 50 „ 

 3 hrs. 



3 



5-3 

 7-6 

 9-4 

 11 -3 

 21 -5 



3 



2-3 

 2-3 

 1-6 



1-9 



8-5 

 15 -5 

 22 -7 

 29 



35 9 

 86 -1 



8-5 

 7-0 

 7-2 

 6-3 

 6-9 



