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



Table V. — Showing Effect of Molar and Decimolar Solutions of Sodium 

 Chloride. 



Time, in 



Cubic centimetres of carbon dioxide evolved from 

 5 grm. yeast and 20 c.c. of solution. 











NaCl, molar. 



NaCl, decimolar. 



Water control. 



1 



2 

 3 

 4 



5 



37 -5 

 57 -4 

 66 -6 



70 -8 



71 -7 



11-2 

 17 -4 

 21 -4 

 23 -9 

 26 1 



12 -6 

 18 -2 

 21 -5 

 23 -8 

 26 -1 



It follows that sodium chloride solution is without influence upon the auto- 

 fermentation when the concentration is so low as to produce no plasmolysis of 

 the yeast. 



Experiments were, therefore, made to determine the effect of iso-osmotie 

 solutions of various substances, which had all been found to produce plasmo- 

 lysis in a similar manner to sodium chloride. The osmotic coefficients were 

 taken from the tables given in Pfeffer's ' Physiology of Plants,' and in some 

 cases the freezing points of the solutions were determined. The results are 

 given in the following tables : — 



Table VI. — Effect of Iso-osmotic Solutions of Salts. 





82. 









83. 









A. 



B. 



C. 



D. 



A. 



B. 



C. 



D. 



Details 





10 grm. pressed yeast + 20 c.c. 



of solution. 





Substance em- 



NaCl 



K 2 HP0 4 



CaCl 2 



Water 



NaCl 



E 2 S0 4 



Mannitol 



Water 



ployed 









control 









control 



Concentration ... 



Molar 





8'3 grm. 





\ molar 



6 5 grm. 



13 5 grm. 









100 c.c. 



100 c.c. 







100 c.c. 



100 c.c. 





Time, in hours. 



Cubic centimetres of carbon dioxide. 



Cubic centimetres of carbon dioxide. 







0-5 



18 -3 



19 -6 



19 -5 



10 -5 



14 -6 



13 3 



12-7 



10-5 



1-0 



31 -8 



33 -3 



33 -5 



16 -4 



24-0 



22 -0 



21 -0 



16 -4 



1-5 



42 -1 



42-7 



43 -3 



20-9 



30-8 



28 -0 



28 -2 



20-9 



2 -0 



49 -3 



49-3 



50 -5 



24-8 



36-0 



32 -7 



31 -8 



24 -8 



2-5 



53 -6 



53 -3 



54 9 



27-8 



39 -2 



35 -5 



34-6 



27 -8 



3-0 



57 -3 



56 -5 



58 -5 



30 -8 



41 -7 



38 -0 



36 "8 



30 -8 



4-5 



62 -0 



61 -2 



64 -3 



36 -8 



45 -7 



43 -0 



41 -5 



36 -8 



