Microbes in fermentation, putrefaction, and disease / by Charles Cameron.

Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: Microbes in fermentation, putrefaction, and disease / by Charles Cameron. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    corpuscles will fall to pieces, and salts will crystallise out, but it will not putrefy. Wort will oxidize, but it will not ferment; and animal and vegetable infusions will remain for years without apparent change. But, in establishing these facts, it has been proved that the most extraordinary difference exists between the tenacity of life exhibited by the developed microbes and the spores or germs from which they spring. Submit the microbes to a boiling heat, or, in many instances, to a heat far short of the boiling point, and they are killed. Dry them, and in many cases they die at once, and in all in a comparatively short time. Expose certain of them to the oxygen of the air, and they perish. Saturate the fluid in which others are found with carbonic acid, and they are paralysed; and though for a time capable of revival by oxygen, ultimately succumb. Expose any of them to oxygen under high pressure, and they are asphyxiated. Dilute solutions of antiseptic agents kill them. But as to the S}Dores which they produce, and from which succeeding generations spring, there is almost no killing them. The more you dry them the better they resist destruction. Time is no object with them, and they maintain their dormant vitality for an indefinite number of years. Absolute alcohol has no effect on them. As to oxygen, they can stand that concentrated by the pressure of twenty atmospheres, and be none the worse. Two or three hours’ boiling, if they have been well dried beforehand, seems not to hurt them, and they have been even known to survive eight hours of the process. The only effectual means for their immediate destruction that I am aware of is the flame of a spirit lamp. To that their extreme minuteness renders them an easy prey. Now, how, you will ask, does it come, when these germs can stand so much rough handling without destruction, that mild solutions of such harmless antiseptics as carbolic acid or borax, or per- manganate of potash, can havo any effect in preserving us