156 



Mr. W. N. Hartley on the 



[Feb. 8, 



how are we to account for the action of various antiseptics? In the 

 Report to the Cattle- Plague Commissioners " On Disinfection and Disin- 

 fectants/' by Dr. Angus Smith, an account is given (p. 10) of the action of 

 a number of essential oils, such as oil of bitter almonds, oil of mustard, 

 amylic alcohol, cresylic and carbolic acids, and ether, the vapour of which 

 was diffused in air surrounding pieces of meat. Many substances had the 

 property of preserving the meat for a great length of time, especially 

 amylic alcohol and oil-of-bitter-almonds chloroform ; and carbonic tetra- 

 chloride also shares this property. If these nitrogenous particles are not 

 living things, how are we to account for the action of the substances ? It 

 cannot be a chemical action, because these substances are chemically in- 

 active. In some cases the less active colytic agents having diffused away 

 out of the bottle, mould formed on the meat, or putrefaction commenced ; 

 and this always happened on that part nearest the cork, showing that 

 particles causing the change came in with air after the preservative agent 

 had escaped. That these colytic agents were fatal to the growth of mould, 

 or the spread of putrefaction, was ascertained by placing mouldy paste under 

 a bell, the atmosphere of which contained a small quantity of the vapour. 



It has been doubted lately whether carbolic acid has the power of de- 

 stroying germs, whether, in fact, Prof. Lister's surgical treatment depends 

 upon this power. The experiments which have given rise to the question 

 tell us only that when carbolic acid is added to a putrescible liquid it is not 

 preserved. There is nothing new in this. " The phenylic and cresylic 

 alcohols, which experience has shown to be generally so active in the pre- 

 vention of putrefaction, are not sufficiently constant when a large quantity 

 of water is present" *. When in a state of vapour very greatly diluted with 

 air, we find them preventing organic growths and putrefaction in an extra- 

 ordinary manner. In order to preserve liquids, corrosive sublimate, sul- 

 phate of copper, and chloride of zinc are the most efficacious substances. 



If those particles which are the origin of life are themselves lifeless, they 

 could not influence the nature of the organisms developed ; in that case 

 different solutions would give rise to different organisms, and, conversely, the 

 same solution would yield the same form of life. But we do not find this 

 to be the case ; for in the same infusion of turnip in Experiment D" 1 and 

 D" 3 occur on exposure to the air at different times different forms of life. 

 In the one case minute vibriones and masses of Torula-celh occurred, 

 whereas in the other confervoid growth and some minute motionless or- 

 ganisms which had not previously been observed were the most noticeable 

 forms. With different portions of a solution of alkaline phosphates and 

 tartrates, in one case we got a fungoid and in the other an algoid form of 

 life. Were it not for the great preponderance of sound experimental evi- 

 dence to the contrary, it would be easier to believe the theory that life was 

 evolved de novo. It is the crude idea which a superficial observer of everv- 

 day phenomena would entertain ; the popular error that maggots are bred 

 * " On Disinfection and Disinfectants," Cattle-Plague Report, pp. 14 & 15. 



