INDIAN COEN. 353 



depend on the appropriating power of each species. For 

 instance, the sweet corns take twice as much of the phos- 

 phates from the soil as white flint. Yet, these two have 

 been planted together, and grains of each found on the same 

 ear. Let these grains that grow side by side on the same 

 ear and stalk, that received the same nourishment, be split 

 and immersed in a solution of sulphate of copper, and the 

 green color given indicates more than double the amount of 

 phosphate in the sweet than in the flint. 



Take specimens of grains split as before directed and 

 immerse them in tincture of iodine, and the limits of starch 

 and dextrine will be exactly defined, the iodine making an 

 intense blue with the starch, and a port wine color with the 

 dextrine or gum. The horny covering of the grain has 

 so 'much oil combined with the gluten, its chief element, 

 that it is protected from the action of the re-agents, though, 

 if the oil be extracted by immersing in alcohol, the starch 

 will be seen in this portion also. By these and the before- 

 mentioned experiments, the precise amount of the phos- 

 phates, oils, irons, dextrine and starch can be ascertained 

 in each variety, and thus the farmers will be able to apply 

 the precise elements requisite for the formation of the 

 grain. 



Now, one of the practical results of the knowledge ob- 

 tained is, that the more phosphates contained in corn, the 

 more osseous or bony matter supplied to the animal fed 

 with it ; hence old animals fed largely on corn are disposed 

 to gout or stiffness, which is produced by the deposits of 

 the superabundance of bony matter in the joints, forming 

 small concretions of phosphate of lime. Every one has 

 noticed about the knees of old horses these knots. 



With regard to the relative proportions of starch in the 

 different varieties of corn, it has been observed that the 

 white soft corns contain the most, but contain little or no 

 oil or gluten. The Mexican Black is likewise chiefly com- 

 posed of starch, while the Yellows have a large proportion 

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