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36 through their changes in anything like order, and show only extremely high, light, and puffy heads. Frequently the attenuation or decrease of specific gravity altogether stops; and the beer becomes sour, or partially unsound, before leaving the fermenting tun. A rather singular attendant on this galvanic action in the fermentation is, the rise of the temperature of the worts in the fermenting tun will, in the course of one night, be 10 or 12 degrees, or more, and without a corresponding attenuation; while, in all healthy fermentations, there is a regular and proportioned decrease of gravity for increase of temperature. This is a point (although at present very little known or attended to) of the utmost consequence in regulating the proper quantities of yeast to be employed as a ferment, according to the specific gravity of the worts, and quality of the beer to be produced. A great deal of attention has of late years been bestowed on the mechanical construction of the utensils employed in breweries, in order to diminish manual labour and the waste of beer, and in making them quite automatic. In these improvements, unfortunately, too little attention has been paid to the injurious action of galvanism, or electricity. We know of one exception. An extensive establishment in London, well aware of the action induced by electricity, took the wise precaution, a few years since, when erecting fermenting tuns, containing 1400