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bury, respecting the saline and other ingredients of Zea 

 mays, and other grains, exhibiting specimens of seeds to 

 which Mr. Hayes' test of sulphate of copper, for the detec- 

 tion of the limits of the phosphates, had been applied. He 

 also exhibited specimens to which tincture of iodine had 

 been applied, which indicated the extent of the starch in 

 each kind of grain and in several other plants. Mr. Hayes' 

 discovery of the limits of a salt of the peroxide of iron 

 was demonstrated by soaking Indian corn in sulphydrate 

 of ammonia. 



The relative proportions of oil in the different varieties 

 of corn was shewn by sections of the kernel, also the rela- 

 tive proportions of the zeine of Gorham or the gluten of 

 corn. The causes of the peculiar explosion and evolution 

 of the starch and gluten of corn in parching, was explained 

 by the decomposition of the oil in the cells of the transpa- 

 rent portions of the grain. 



Dr. Jackson had observed, in April, 1840, while analyzing the 

 ashes of Indian corn, that after combustion of the corn in a plati- 

 na capsule, at a high temperature, the platina was rendered brit- 

 tle, and was in part converted into a phosphuret of that metal. On 

 examining into the cause of this, he discovered phosphoric acid 

 united to some volatile or destructible base, mixed with the phos- 

 phates of lime and of magnesia. 



His subsequent researches satisfied him that the volatile base in 

 question was ammonia, which he separated by the action of potash 

 and lime, at a temperature below that required for charring the 

 grain. 



By the action of nitric acid, he burnt out the carbonaceous mat- 

 ter from the ashes of corn, and procured a considerable quantity 

 of glacial phosphoric acid. In all these experiments, thus far, the 

 whole grain was employed. 



In May, 1842, Mr. A. A. Hayes, of Roxbury, exhibited to the 

 chemical association some specimens of southern corn, which had 

 been cut in two and soaked in a solution of sulphate of copper ; 

 and this test most beautifully marked out the limits of the phos- 

 phates in that grain. Profiting by this interesting experiment, and 

 observing that the phosphates were indicated only in the cotyledon 

 of corn, Dr. Jackson dissected out the cotyledons, analyzed them 



