no Fermentation and Kindred Phenomena. 



living organisms, the reason for the action of antiseptics and 

 disinfectants became intelligible. It then became apparent that 

 they act as poisons on the organisms 



I do not desire to detain you long on this subject, but there 

 are certain points connected with it of considerable importance 

 which I ought to touch upon. If we take a putrefying liquid 

 and add to it a very small quantity of carbolic acid, corrosive 

 sublimate, chloride of zinc, &c, the putrefaction stops. The 

 organisms are poisoned, and consequently they perish. Simi- 

 larly, after a case of an infectious disease, sulphur is burnt in the 

 room occupied by the patient, or chlorine is evolved from 

 bleaching powder, everything is well washed with carbolic acid, 

 and the bedding is burnt. 



Have all the disease organisms or their spores been destroyed ? 

 I am decidedly of opinion that they have not, and chiefly for 

 this reason : that the spores of an organism have an extra- 

 ordinary power of resistance to destructive agencies. Thus the 

 spores of the hay bacillus can be completely dried, and can 

 actually be boiled with water for a considerable time without 

 losing their vitality. It might be argued that the hay bacillus 

 is not a disease organism, and that the latter are more easily 

 destroyed. Possibly this is the case with some, but certainly 

 not with others. Thus it has been proved that a solution of 

 corrosive sublimate — the most powerful antiseptic we are ac- 

 quainted with — stops the growth of the spores of bacillus 

 anthracis, even when the solution contains only one part of cor- 

 losive sublimate to 300,000 of water. But, on the other hand, 

 the spores have not lost their vitality, for Klein has shown that 

 they may be soaked in a one per cent, solution of corrosive sub- 

 limate for twenty-four hours, and yet when removed and 

 injected into animals the latter soon die of tpyical spleen fever. 



Several years ago Professor Fuller and I tried a number of 

 experiments on the action of gaseous antiseptics, such as 

 chlorine, bromine, the fumes of burning sulphur, ozone, &c, on 

 putrefactive organisms, or rather on their spores, and we were 

 simply astonished at their power of resistance. Bromine ap- 



