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MASSACHUSETTS HORTICULTURAL SOCIETY. 



Kernels of wheat, if ground and mixed into dough, and this 

 dough washed for a long time in water, give a tough, gluey sub- 

 stance known as gluten. 



A piece of sugar beet if boiled in alcohol yields, on drying 

 away the alcohol, sugar. 



Any plant if subjected to the consuming flame, leaves behind 

 an indestructible part called ash. Now all plants have most of 

 these substances ; in some, one predominates ; in others, other 

 parts are prominent, e. g. sugar in the beet, starch in the potato, 

 oil in cotton seed, etc. For the purpose of bringing out more 

 clearly the facts thus far stated, I have given below the composi- 

 tion, in pounds per acre, of two crops — one Ensilage, yielding 

 twenty tons per acre ; the other Hay, yielding two tons as cured 

 and put in the barn. 



408 



180 



(2.) Source of these Substances. — Plants do not find sugar, 

 starch, etc., in the soil, nor in the air, but the}' do find, either in 

 the soil or air or both, the elements from which to make these 

 materials. Water comes from the air as rain or snow, is stored 

 in the soil and taken up by the roots of the plant, and, as this 



