654 CONDITIONS AFFECTING THE DEATH OF FUNGI. 



Distinct hindering of Complete cessa- 



growth tion of growth 



Occurred when the concentration reached 



Salicylic acid 1 



Benzoic 1 



Carbolic 1 



Benzoate of soda 1 



Camphor 1 



Quinine 1 



Alcohol 1 



Common salt ... 1 



3,300 1 : 1,500 



2,000 



1,250 1 : 850 



200 



2,500, over 1 : 1,250 



830 1 : 625 



100 1 : 12-5 



64 .. 



Action of A series of experiments by Kichet* may also be mentioned 



various where the fluid employed was a mixture of 900 erammes of 



metallic salts 1AA ,. , n & ^ 



sea-water, 100 grammes or neutralised urme, and 1 gramme 



of peptone, the attempt being made to ascertain how much 

 of the various metallic salts it was necessary to add to this 

 solution to prevent the development of bacteria. In the 

 following table the amount of the pure metal has been calcu- 

 lated from the amount of the metallic salt which it was 

 necessary to add to each litre of fluid, and also for comparison 

 those figures are given which correspond to the quantity of 

 metal per litre which was necessary to kill salt water fish. 

 From this comparison we see at once the much greater 

 resisting power of the bacteria, and also the unequal behaviour 

 of certain metallic poisons in reference to the animal and 

 vegetable cell. 



Amount of metal per litre of fluid 

 To hinder the development To kill fish, 

 of bacteria. 



Mercury 0'0055 gramme . . . 0'00029 gramme 



Zinc 0-026 ... 0'0084 



Copper 0-062 ... 0'0033 



Iron 0-24 ... 0'014 



Barium 3'35 ... 078 



Manganese 77 ... 0*3 



Ammonium 187 ... 0'064 



Calcium 30'0 ... 2'4 



Sodium 43-0 ... 24'0 



Potassium 58*0 ... 01 



Of the inhibitory substances not included in the foregoing 

 tables, but which have been tested and recommended, we may 

 mention the following : 



Other According to the experiments of Wassilefff calomel has an 

 disinfecting 



substances. , , _ 



* Compt. rend., vol. 97. 



f Zeitschr.f. physiol. Client,, vol. vi. 



