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dian com, which had been grown about two inches high, in pure 

 powdered quartz. The changes which the seed had undergone 

 were quite interesting, and it was seen, by the iodine test, that the 

 starch of the albumen had been absorbed, and was changed in the 

 plumule into dextrine and sugar. The portion of the corn, where 

 the oil exists with starch and gluten, had begun to change, and 

 iodine instantly forms a blue compound with the starch. On ap- 

 plying the sulphate of copper, the presence of phosphoric acid in 

 the radicle and plumule, and a little around it, was readily proved. 



On testing germinated English beans, the presence of phos- 

 phates was demonstrated in the cotyledons, but iodine did not 

 prove the formation of starch from the legumin. The same ex- 

 periment was performed with the common bean, with the same re- 

 sults. It will be interesting to study the changes which legumin, 

 (a substance now supposed to be identical with caseine,) undergoes 

 in the process of germination. As yet, we know of no chemical 

 researches on its transformations in the living plant. 



Dr. J. had observed that cucurbitaceous plants contained nitrate 

 of potash, and had consequently directed its application around 

 the roots of such vines. Observations on such plants grown on 

 nitrous ground, where old barns had been removed, proved the 

 value of that salt as a manure for squashes, pumpkins and melons. 



Many important and interesting agricultural principles are to be 

 discovered by investigations similar to these above noticed, but it 

 may not be appropriate to lay any other facts before this Society 

 than such as appertain to Natural History. It is evident that 

 Organography and Physiology may derive much aid from the 

 application of chemical tests to plants and their fruits. The sub- 

 ject is yet in its infancy, and we have much to expect when it 

 shall become more mature. 



Dr. Jackson exhibited to the Society a buff-coloured salt 

 of lead, obtained by him, in 1841, from the maple sugar 

 of commerce, by adding to its solution sub-acetate of lead. 



This salt is humate of lead, and demonstrates the existence of 

 humic acid in maple sugar, in which it was combined with ammonia 

 and lime. March 18th, 1842. —Flavin g procured some maple 

 sugar made with care at Northampton, he repeated his researches, 

 and discovered in it humic acid, apocrenic acid and crenic acid. 

 These acids were proved to be combined, in part, with ammonia, 



