264 PROCESS OF MALTING. 



dinary circumstances, is quite useless in diminishing 

 the quantity of that substance contained in the 

 seeds : its presence in the air is, however, very use- 

 ful, serving to dilute the oxygen and to prevent 

 its acting too rapidly. Seeds are found to germinate 

 very quickly in pure oxygen gas, but the plants pro- 

 duced are weak and unhealthy. 



689. The germination of seeds may be readily 

 effected in water, although they are for the most part 

 unable to grow and vegetate under that fluid. The 

 change which, under ordinary conditions, is effected 

 in seeds by the oxygen of the atmosphere, is, under 

 these circumstances, caused by the oxygen of the 

 small quantity of common air always dissolved or 

 held in solution by water. In no case can a seed 

 germinate unless free oxygen is present, or some 

 other means exist by which a portion of the carbon 

 in the seed can be removed, so as to cause the change 

 in the constituents of the seed before described. 



690. In the process of malting, or converting raw 

 grain into malt, the object to be attained is to change 

 a large portion of the starch which the barley con- 

 tains into gum and sugar. This is effected by steep- 

 ing the grain in cold water, and then heaping it up 

 together on the floor of the malt-house ; it is thus 

 placed in the most favorable conditions for germ- 

 ination, and consequently the chemical changes 

 attendant on that process immediately commence. 

 The seeds lose carbon, and at the same time convert 

 the oxygen of the air into carbonic acid ; the embryo 



