94 Oil Disinfectants. 



attention to tlic fact that wo have to deal with a very subtle but material 

 body, whether disinfection or cure be our object. 



I j)ropose to make some observations on — 



1st. The various disinfectants recommended by different persons, 

 their mode of action, and their comparative efficacy. 



2nd. The application of disinfectants, to particular purposes, as 

 the disinfection of cow-sheds, carriages, trucks, manure -heaps, &c. 



3rd. Preventives : an inquiry which would have special reference to 

 disinfectants in relation to the Cattle Plague. 



With respect to the word " disinfectant," very vague and confused 

 notions are prevalent : and it would be well if the word were confined 

 solely to those solid, liquid, or gaseous materials which possess the 

 power of disorganising or destroying all matter capable of reproducing 

 disease in animals ; frequently, however, the word is applied to sub- 

 stances which, though they remove disagreeable gases and vapours, 

 such as- those produced by sulphuretted hydrogen, fail to destroy 

 the cause and source of the nuisance : properly these are deodor- 

 isers, not disinfectants ; and of these there are many. But the appli- 

 cation of chlorine or nitrous acid, not only removes the smell pro- 

 ceeding from frecal matters, but breaks up or destroys the organic 

 matter and resolves it into ultimate gas products, comparatively harm- 

 less, as completely as fire could do. Chlorine and nitrous acid, there- 

 fore, are not merely deodorisers, but true disinfectants ; and such 

 substances are always deodorisers, although deodorisers are not always 

 disinfectants. 



Agents used to prevent or retard that putrefaction which gives rise 

 to foul odours, are often regarded as disinfectants. If, however, a 

 disinfectant be that which breaks up and destroys the constitution of 

 organic matter, the term is inapplicable to substances which, instead 

 of hastening destruction, preserve organic matter from disorganisation. 

 Such substances are, properly sj)eaking, antiseptics. Thus, carbolic 

 acid, creosote, and other preparations of tar, which, in minute quan- 

 tities, are capable of preventing the putrefaction of meat, blood, urine, 

 and other animal matters exceedingly prone to enter on decomisosition, 

 are true antiseptics, and the very reverse in their action to disin- 

 fectants, such as chlorine, and nitrous acid. It is true that, in a con- 

 centrated state, carbolic acid and creosote are strong destroyers of 

 organic matter ; but it must be borne in mind that, in such a form, they 

 could not practically bo used for disinfecting purposes. Moreover, in 

 common parlance, the term disinfection is applied to substances Avhich 

 merely deodorise j)laces from which foul gases emanate ; and this is 

 much to be regretted, because such a use of the word involves con- 

 fusion of ideas and errors in practice. I call disinfectants, therefore, 

 those substances which destroy all matter capable of producing dis- 

 ease ; deodorisers those which neutralise foul gases without destroying 

 the organic bodies from which they emanate ; whilst substances em- 

 ployed to prevent or impede putrefaction I call antiseptics rather 

 than disinfectants. 



