Researches on Micro-Organisms; Including an Account of Recent Experiments on the Destruction of Microbes in Certain Infectious Diseases, Phthisis, Etc (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1891 Excerpt: ...the mixture. Twelve dry sterilized tubes (Fig. 22), not hermetically sealed, also contained the same quantity of the mixture of sputum, calcium sulphate, and calcium carbonate (these mineral substances constituting the principal ingredients contained in the dust of the atmosphere). The twenty-four tubes were kept at a dry heat of 32 C., from one to six months. Two of the hermetically-sealed tubes and two of the open tubes were opened after being exposed to the above temperature for one month; and four tubes, containing sterilized blood serum, were inoculated from the contents of the tubes. In the two inoculated from the open tubes growths of Bacillus tuberculosis (proved by staining, microscopical appearance, etc.) made their appearance in sixteen days after the inoculation. Growths of Bacillus tuberculosis also made their appearance in the two tubes inoculated from the contents of the sealed tubes after nineteen days' incubation. Four more tubes were opened after being exposed for two months at the temperature already mentioned. Inoculations from two open tubes revealed the vitality of Bacillus tuberculosis after twenty days' incubation; and inoculations from two sealed tubes proved the vitality of the bacilli after the lapse of twenty-three days' incubation. The remaining tubes were examined in a similar manner after the lapse of three, four, five, and six months respectively. After being exposed to the dry heat for three and four months, this microbe and its spores were not destroyed. But after being heated for five and six months B. tuberculosis and its spores were completely destroyed; for no rgrowths made their appearance in sterilized blood-serum kept at a temperature between 37 and 39 C. for nearly two months. From these experiments it appears that ...