TOXICOLOGY AND PHARMACOLOGY 



367 



trodes by electric arcs under water). They stabilized some of their 

 solutions with pure gelatin. 



Since CREDE'S publication the literature on the action of colloidal 

 silver has become extremely extensive, and the results are very con- 

 tradictory. It was at first employed in septicemias, by some, with 

 professedly good results, and by others without any apparent influ- 

 ence. I have personally interviewed many practitioners of medi- 

 cine on the action of colloidal silver and have found among them 

 similar contradictions. Some were enthusiastic advocates of col- 

 loidal silver therapy at first, but after several failures dropped the 

 use of colloidal silver entirely. E. FILIPPI is possibly correct in at- 

 tributing a therapeutic result only to a single dose. [A similar ob- 

 servation has been made in connection with non-specific therapy by 

 intravenous injection of typhoid vaccine in rheumatism. Tr.] He 

 emphasizes the decided difference in the hydrosols of different metals, 

 so that the hydrosol of the one most suitable must be selected for each 

 individual case. Colloid silver is not only said to be active in general 

 infections, but it has been praised also in local processes. VON 

 OETTINGEN, who served in the Russo-Japanese war, recommends it 

 heartily as a disinfectant for wounds. [MACDONAGH has used col- 

 loidal manganese. Tr.] 



Action on Microorganisms. 



The action of colloidal metals on protozoa (paramecium, vorticella, 

 opalina) has been studied by E. FILIPPI. 



It is noteworthy that the lethal threshold for salts of the same 

 metals are very similar for the same dilution and for the same con- 

 tent of metal. 



Colloidal silver has absolutely no effect on moulds. I found that 

 a 1 per cent collargol solution which had been left unstoppered was 

 covered after a time with a species of mould. Similar observa- 

 tions were made by FILIPPI * with penicillium and aspergillus in the 

 case of different colloid metals. R. ZsiGMONDY* 1 mentions that 

 moulds grew on his gold hydrosol and that the solutions were grad- 



