238 



Dr. G. Thin. 



3. Milk. — The milk used liad been purified by boiling in a water 

 bath, and had been kept pure in purified glasses, according to the 

 method described by Mr. Lister.* 



The results of the experiments were negative, but are in other 

 respects interesting. 



A hair from a patch of ringworm was placed on the surface of milk, 

 in a glass otherwise kept pure and set aside at the room temperature 

 on the 16th March. It was taken out on the 27th, a fungus growth 

 having been visible to the naked eye for several days. The root of 

 the hair was found enveloped in Penicillium glaucum. When the hair 

 had been macerated in a solution of potash it was seen that it had been 

 healthy, and it contained no ringworm spores. 



Two hairs, which turned out to be ringworm hairs, were kept on the 

 surface of milk for eighteen days. There was large development of 

 fungus, but I could obtain no evidence that it had any connexion 

 with the ringworm spores. A supposed ringworm hair, after being 

 on the surface of milk for three days in the incubator was found 

 enveloped in fungus, but maceration in potash showed that there 

 was no trichophyton in the hair. A ringworm hair in a tube at the 

 bottom of the milk glass in two days in the incubator had developed 

 nothing. 



Two experiments showed that even with milk the development of a 

 fungus does not necessarily follow when protected pure glasses are 

 used. 



A supposed ringworm hair was placed on pure milk in a protected 

 glass in the incubator for three days. No fungus of any kind grew, 

 and maceration of the hair in potash showed that the hair was not 

 affected with trichophyton. Another supposed ringworm hair, but 

 which subsequent examination showed to contain no spores, was 

 placed in pure milk in a protected glass for thirteen days without any 

 fungus developing. 



My attempts to grow trichophyton in milk thus failed. 



In connexion with Mr. Lister's experiments on the lactic fermenta- 

 tion, it may be worthy of remark that the glasses used were all charged 

 with pure milk by the method he has described, and that the milk 

 remained unchanged until they were used for these experiments. 

 With the introduction of the hairs bacteria were necessarily also 

 introduced, but the glasses being immediately protected, no other 

 bacteria than those adhering to the hairs were present. The hairs, 

 after they were extracted from the patients' heads, had been kept in 

 paper until they were brought in contact with the milk. Various 

 although usually very slight changes took place in the appearance of 

 the milk, but in none of the glasses did the common lactic fermenta- 



* " On the Lactic Fermentation." " Transactions of the Pathological Society of 

 London," vol. xxix. 



