A parasitic or germ theory of disease : the skin, the eye, and other affections / by Jabez Hogg.
- Jabez Hogg
- Date:
- 1876
Licence: Public Domain Mark
Credit: A parasitic or germ theory of disease : the skin, the eye, and other affections / by Jabez Hogg. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![i i was almost entirely due. It would be more trustworthy | i if comparisons of this kind could be made at the same i stage of development; for be it remembered that yeast h i obtained from a brewery is in a more favourable state for || * experiment, inasmuch as it is stopped at a certain stage U of growth or development, and then set to begin its fer- t\ mentation over again in fresh supplies of a new wort or I; pabulum, which gives increased health and vigour to the | plant; whereas the favus fungus is obtained and used | in an exhausted state, and taken from an ill-nourished or starved soil. Neither must we attach much import- ance to differences in size and form of the spores, as this also occurs in yeast ferment; the ovoid form, : although most frequently seen in achorion, is equally i common to yeast when exhausted. To ensure success in these and similar experiments, the fungus or yeast should be left floating on the surface of liquids; fermen- tation is either carried on very slowly or is entirely arrested by submersion. Turpin and others, experimenting with yeast, noticed in every case that the cells become oval and bud out in ; about an hour after being added to the wort; this how- * ever quite depends upon temperature and density of ; solution, as well as upon the quality of the yeast. It is : a fact that when yeast is added to distillery wash, which iis always worked at a higher temperature than brewers’ 'wort, fermentation commences earlier, and the yeast- < cells grow to a much larger size. It is in this way forced much as a plant in a hothouse is, and obtains to greater ] perfection in a shorter time ; but if again used as a i ferment it is sooner exhausted, and therefore, if a small portion of this yeast be added to barley-wort and kept at a temperature of from 60° to 65° Fahr., it ferments lan- guidly, and small yeast-cells are the result. If the yeast is allowed to stand in a warm place for a few days, it partially recovers its activity, never wholly. With such](https://iiif.wellcomecollection.org/image/b22309342_0061.jp2/full/800%2C/0/default.jpg)
