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without fear of alcoholic loss, and with a considerable economy of 

 fuel. All the various parts of the apparatus are made to separate 

 so as to facilitate its taking to pieces, which is indispensable for 

 work subject to be frequently put aside and sometimes for a certain 

 length of time. 



The second illustration shows another type of the same 

 pasteuriser, constructed by the same makers. 



Another method, more efficacious and less objectionable, is to 

 make a free use of sulphur fumes. 



Instead of sulphur fumes, some chemical substances, such as 

 sulphites, holding sulphur in a loose state of combination, may be 

 substituted with advantage. For instance, sulphite of soda or bisul- 

 phite of potash, at the rate of one to two ounces per 100 gallons, 

 simply dropped into the wine, which after a day or so may be stirred 

 a bit and allowed to rest, generally remove in four or five days the 

 objectionable casky taste, whilst neither the colour, the taste, nor 

 the smell remain affected either by the defect or the remedy 

 employed. 



It consists in destroying by heat the micro-organisms in the 

 liquid. These micro-organisms, like those we have already con- 

 sidered when dealing with ferments, are made of living albumen 

 (protoplasma), encased in a covering of cellulose. Like the yeast 

 of fermentation, they are also provided with spores, which are germs 

 of reproduction more resistant than the protoplasma itself. 

 Heat, when raised to 75 C. (167 F.), coagulates the living 

 albumen, and if that temperature be maintained for a longer period, 

 kills the spores as well. 



The acidity, strength, or alkalinity of the liquid these germs 

 are immersed in also influences the degree of heat required to 

 destroy these living germs. Thus, in fresh grape must before 

 fermentation, a temperature of 75 to 85 destroys all the organisms 

 present. 



In the resulting wine, after fermentation, however, a tempera- 

 ture of 60 C. (140 F.) will achieve the same result; here the 

 action of heat being strengthened by the presence in the wine of 

 both the acids and alcohol. 



In a substance like milk, on the other hand, which is at the 

 same time alkaline and fatty, the temperature has to be raised to 

 about 110 C. or even higher to sterilise the liquid. 



The diseases of wine being caused by living germs or bacteria, 

 which can only be seen with the help of a powerful microscope 

 magnifying 600 to 900 times, it is natural to classify them into 

 groups suggested by the characteristic behaviour of these bacteria 

 themselves. 



The mere presence of these bacteria into the wine does not in 

 itself cause that wine to be undrinkable or unwholesome, but it is 

 the accumulation into it of noxious matters produced by the 

 bacteria, as well as the suppression by these of matters essential to 



