258 Mr Rudge, On the Action of Radium 



On the Action of Radium and other Salts on Gelatin. By 

 W. A. Douglas Rudge, M.A., St John's College. 



[Read 29 January 1906.] 



On October 31st I gave a short account of some experiments 

 which I had made on the action of radium salts on gelatin. The 

 present communication is a more detailed account. 



If a small amount of a radium salt is sprinkled upon the 

 surface of some sterilised gelatin, a rapid change is seen in the 

 appearance of the latter where the salt touches it. A whitish 

 sort of patch is formed under the radium and this patch extends 

 and becomes nebulous and like an ordinary fungus or mould in 

 appearance. The growth goes on for about two days. 



The most convenient means of examination was to place the 

 gelatin upon a glass slip, add a speck of radium preparation, 

 cover with a thin glass and examine with a half-inch power. It 

 was then seen that around the radium the gelatin liquefied and 

 a copious evolution of gas bubbles took place. At the same time 

 a sort of " growth " appeared, quite distinct from the bubbles, 

 and spread round the particle of radium. The growth seemed 

 like a mass of micrococci, and it slowly extended, reaching a 

 maximum in about a day. On examining the growth with a 

 high power, it appeared to consist of a collection of cells resem- 

 bling starch granules, and after a day or two something like a 

 nucleus could be seen. 



The idea has been advanced that these cellular growths were 

 in some ways analogous to living cells. 



Many groups of cells could be seen, and especially pairs which 

 looked as though a single cell had divided into two, but very 

 careful watching showed no signs of any fusion actually occurring, 

 and the fact that a "dumb-bell" arrangement was frequently 

 found, appeared to the author to be purely fortuitous. 



As radium preparations are composed chiefly of barium it 

 seemed likely that salts of the latter metal might be capable of 

 acting on the gelatin, and on putting the matter to the test this 

 was seen to be the case, and a growth was obtained which could 

 scarcely be distinguished from that caused by the radium. 



A close examination was next made with most of the metallic 

 salts available in the laboratory, and besides radium and barium 

 only strontium and lead salts yielded any definite results. 



Now gelatin contains sulphur as an essential constituent, and 

 in the course of manufacture is, I believe, treated with sulphur 



