272 FROTH. 



A. Because fruit contains carbon, 

 hydrogen, oxygen, and nitrogen, in the 

 form of "gluten;" and, therefore, fer- 

 ments spontaneously. 



(Gluten is explained fully in the Appendix. Turn 

 to the word in the Index.) 



Q. Does not MALT contain carbon, hydrogen, 

 oxygen, and nitrogen, as well as FRUIT? 



A. No; the sugar of malt contains 

 carbon, hydrogen, and oxygen, but no 

 nitrogen; in consequence of which, 

 yeast (which contains nitrogen) is added 

 to the wort. 



Q. Why do NOT GRAPES ferment while they 

 hang on the VINE ? 



A. 1st Because the skin lets out 

 the water of the pulp, which causes the 

 grapes to shrivel and dry up : and 



2ndly The skin prevents the admis- 

 sion of oxygen into the pulp, from the 

 air without. 



Q. Wliat is the FROTH or SCUM of fermented 

 LIQUORS ? 



A. Carbonic acid gas, which (being 

 heavier than common air) settles on the 

 top of the liquor, in the form of scum. 



