This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
Microbe and Bacteria being frequently found in polluted water, an explanation of the terms is necessary. By the term microbe is understood a microscopic organized germ, which exists in diseased animal bodies, and which, when transferred to other animal bodies, under proper conditions, is capable of reproducing a specific disease, the same as that existing in the body from which it was taken. The cholera microbe thrives in the alkaline contents of the intestines, and when by any means it is transferred to another living body, it is capable of infecting that body with cholera.
On the other hand, when any vegetable or animal infusion, or other liquid containing nitrogenous substances with comparatively little starchy or saccharine matter, is left exposed to the air for some time, putrefactive changes take place, and the liquid becomes filled with minute organized bodies termed bacteria. Various beverages undergo changes of this sort. While these bacteria, together with the substances in which they thrive, may cause sickness if taken into the body, as would any decomposing or putrefactive substance, it is believed these bacteria are not regarded as the cause of any specific disease. Doubtless these two terms have been wrongly used by some writers as if synonymous. With respect to "fermentation" and "bacterial influences," of which we now read so much in connection with diseases and epidemics, the following query occurs: Wine, beer and other beverages go through a fermentation, and they become palatable and desirable. They do not decompose, decay, or create unhealthy or unpleasant exhalations. On the contrary, a carcass of a dead animal is also said to go through a fermentative process, the result of which is the poisoning of the surrounding atmosphere. The "bacterial influences" in these cases are not the same. In one case they act as a preservative and in the other as a destroying agent. Bacteria or microbe are classified. The phenomenon of fermentation is due to a specific germ, or microbe, which always produces the same effects, the microbes being named and classified according to these specific results. The microbe which causes the fermentation of yeast or beer, when put into a proper medium (one containing sugar in some form), decomposes the sugar, and alcohol is one of the results. This microbe is called the torula cerevisice, or saccharromyces cerevisiae, and invariably produces the identical result. The microbe which causes putrefaction is of a different kind, a bacterium known as bacterium termo, or the bacterium of putrefaction.
Interesting experiments as to the rapidity of growth and the means of destruction of microbia, by Dr. T. Leone, a European chemist, are commented on on another page, to which we expressly refer, being exceedingly interesting.