180 MALT LIQUORS. 



contains, and which, if left in the beer, wouhl be very 

 apt to cause its fermentation. 



432. The goodness of ale and porter depends a 

 great deal on the water with which it is brewed ; it 

 is sometimes supposed that the water must be soft, 

 but this does not appear to be really the case, because 

 the water employed in many of the largest and best 

 breweries is decidedly hard, and contains a very con- 

 siderable quantity of sulphate of lime (239). 



433. Porter is essentially ale brewed with a por- 

 tion of scorched or high-dried malt, and the ferment- 

 ation of which has been allowed to proceed so far 

 that nearly the whole of its sugar has disappeared. 

 It was formerly brewed entirely from high-dried malt, 

 but as in that case a large quantity of the sugar 

 was needlessly destroyed, it was found better to use 

 common malt, mixed with a small proportion of high- 

 dried malt ; this gives the desired color and peculiar 

 flavor of porter or brown stout. Sometimes other 

 coloring matters are used for the same purposes ; 

 these for the most part must be regarded as adulte- 

 rations. 



434. The slow, continued fermentation which malt 

 liquors undergo whilst kept ripening in the casks, is 

 essential to their preservation ; because the carbonic 

 acid thus generated protects them from the influence 

 of the air ; hence, too, the casks must be kept closely 

 bunged up to prevent the escape of this gas. As 

 soon as this fermentation ceases, and air gets access 



