On Disinfectants. 103 



sound and nnclianged in colour or general appearance since the 27tli 

 of December, 1865, when the exj^eriment began. 



In the preceding experiments the highest temperature of the room 

 was 61° Fahr., the lowest 53° Fahr. 



In the next place I tried the following experiments, partly with a 

 view of ascertaining whether carbolic acid destroyed or merely 

 masked the foetor proceeding from putrid meat, and partly with a view 

 of ascertaining whether putrid meat is capable or not of tainting fresh 

 meat in an atmosphere strongly impregnated with carbolic acid 

 vapours. 



About -J lb. of putrefying beef was put into a jar, covered with 

 water, and some concentrated carbolic acid was added. The putrid 

 smell disappeared instantaneously, and I am quite satisfied that the 

 smell was not merely masked but completely destroyed by the solu- 

 tion ; for the jar, which previously could not be opened without filling 

 the whole room with an insufterable stench, now gave out no smell but 

 that of carbolic acid perceptible even at its mouth, nor was there any 

 smell perceptible in the further part of the room. 



In the next place ^ lb. of fresh beef was cut into two equal pieces, 

 and \ lb. was suspended in a large wide-mouthed stone jar by means 

 of a wire fixed in the cover of the jar. 



In the course of 4 days the meat emitted so strong and putrid a smell 

 that it had to be removed. 



The second i lb. of beef was susiDended in the same manner and at 

 the same time in a large stone jar, in the bottom of which a piece of 

 putrefying meat was placed, after a little concentrated carbolic acid 

 had been allowed to flow round the sides of the jar for the purpose of 

 imj)regnating the air with the vapours of the volatile acid. 



After a lapse of exactly a month the beef in the second jar is free 

 from taint, but of course smells strongly of carbolic acid and is unfit 

 for consumption. 



Flesh when immersed in a concentrated carbolic acid solution 

 shrivels up and becomes hard like leather. How long it will remain 

 in this condition I have not yet ascertained, but probably for an 

 indefinite period. 



Experiments with Caebolic Acid on Eennet and Milk. 



The object of the following experiment was to determine whether 

 weak and moderately strong solutions of carbolic acid destroyed or 

 left unaltered the peculiar property of rennet to coagulate the casein 

 of milk, or destroyed its active organic principle as chlorine or nitric 

 acid do. 



The solution of rennet which I employed was tested in the first 

 place, as it had been made a long time ago. 



1. A quarter of an oimce added to two ounces of milk thoroughly 

 coagulated the milk in less than 10 minutes. 



2. One-eighth of an ounce of concentrated carbolic acid added to 

 two oimces of milk did not curdle it. 



3. In the next place I added to a quarter of an oimce of rennet 



