vi] Sylvius and his Pupils. 151 



" vehement or of long duration brings about an essential change 

 u or a conspicuous alteration in the fermenting bodies themselves 

 " and is excited so gradually and in so hidden a manner that 

 " while it is taking place it can not be detected by the senses, 

 " and hence is only recognised by the effects which in a given 

 " time it produces. 



" Of this kind is the movement of the particles of a mass of 

 " dough which is beginning to ferment, but which so gradually 

 " liquefies and swells that the change which it is undergoing 

 " is only recognized when after some time it becomes softened 

 " and expanded. 



"Sensible fermentation is the adventitious ****** 

 " bodies themselves and is recognized by the senses so soon as 

 " ever it begins. Such is the fermentation which is brought 

 " about when water is poured on quick-lime, or spirits of vitriol 

 " is mixed with oil of tartar. 



' Vehement fermentation is the adventitious ****** 

 " sensible cause, which quickly brings about an essential change 

 "or a conspicuous alteration in the fermenting bodies them- 

 selves and is produced with a certain impetus and indeed 

 "sometimes with considerable tumult. Of this kind is the 

 " movement which is observed when spirits of vitriol is poured 

 " on oil of tartar or water on quick-lime. 



"Moderate fermentation is the adventitious ****** 

 "which brings about an essential change or a conspicuous 

 " alteration in the fermenting bodies themselves gradually and 

 " without a rush, and with a certain buzzing only (fremitus) or 

 " without any noise or buzzing. 



" Of this kind is that movement which must or wort, as 

 "for instance that of beer, treacle and things of that kind, 

 "undergoes when it ferments, and which takes place with a 

 " certain buzzing. 



" Hot fermentation which properly and deservedly gains the 

 " name of fermentation is the adventitious ****** in the 

 " fermenting bodies themselves, and is accompanied by or quickly 

 " acquires heat. Such is that which is observed when vinegar 

 " is mixed with quick-lime, which indeed is accompanied with 

 "fire and flame and therefore heat. 



