1G2 STATE POMOLOGICAL SOCIETY. 



water, carbonic acid, oxide of iron, chlorides, silicates, magnesia, oxide of man- 

 ganese. 



Water is the most abundant compound in plants. It constitutes 91 parts 

 out of 100 in fresh turnips, 90 of strawberries, 84 of apples, and I'Z out of 

 100 of dry corn. 



It holds in solution the solids, and gases to some extent, much of which are 

 used to build up the plant. 



Plants have the power of decomposing these compounds and of making 

 new materials of them, or of re-arranging them. 



Plants are made up of minute cells. Each cell wall when alive and active 

 is composed of two coats, a thicker outer coat surrounding a delicate inner 

 coat. In wood and bark and some other parts which split or tear into strips 

 or strings, the cells are long, and usually tapering and overlapping at the ends. 

 In the pulp of apples, peaches, shells of walnuts, vegetable ivory, leaves of 

 mosses, all sea weeds and fungi and lichens, and many soft and delicate parts 

 of plants, the cells are not more than two or three times larger in one direction 

 than in the other. The outer cell wall, which alone remains in many mature 

 cells, is composed of cellulose, which is found nearly pure in cells of cotton 

 and fibers of hemp and flax. 



Lignin is found with cellulose in woody fibre and hard shells of nuts, etc. 



Starch is free in the cells of wheat, corn, potatoes, and many other plants. 

 This is the form in which many plants lay up a store of nourishment for fu- 

 ture use. 



Dextrine is starch in a soluble condition. 



All bodies in the cellulose group contain twelve parts of carbon, and ten, 

 eleven, or twelve molecules of water. 



Besides these there is a group of vegetable acids, as oxalic in sorrel, malic in 

 apples, tartaric in grapes, citric in lemons. 



There are fats and oils, resins and wax, containing much less oxygen than 

 exists in the cellulose group. They are mostly composed of oxygen and hy- 

 drogen. 



The alhuminoids or protein bodies da^Q": from the above in containing five 

 elements instead of three. They contain fifteen to eighteen per cent of nitro- 

 gen, a little sulphur, and sometimes a small amount of phosphorus. 



The albuminoids are abundant in seeds and all young growing plants. Al- 

 buminoids exist in the sap of all plants in small quantity. Such parts also 

 contain vegetable fibrin, gluten, caseine. The exact formulae of all these is un- 

 certain. They are easily decomposed. They are very important in food of 

 animals. Albumen is found nearly pure in the white of an egg. 



Chlorophyll (leaf green) exists in small quantities in all parts which are 

 green. It is in the form of granules floating in the transparent cells. Prof. 

 Johnson thinks the quantity of chlorophyll no greater in plants than dye in 

 colored fabrics. 



The above are the materials of which plants are made. They are the bricks, 

 lumber, lime, nails, glass, and paint of the structure. Plants alone absorb in- 

 organic or mineral substances, which are re-arranged or assimilated. With this 

 assimilated material new cells are formed. The plant grows. 



The dreams of those who studied Liebig's writings twenty-five years ago 

 have not been realized. As I understand it, he believed any one could ana- 

 lyze a handful of soil from a field, and then tell just the kind and quantity of 

 fertilizer needed to produce any kind of crops. 



