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NUTRITION OF VEGETABLES. 
fl Jf all the investigations hitherto fiublished on the Theory of Vegeta « 
tion , I know of none that furnishes results so curious , or so impor- 
tant to V egetable Physiology, as the following paper of M. Bra - 
cannot “ On the Assimilating Power of Vegetables abridged 
from the Annales de Chemie , vol. Ixi. p. 187. Feb. 1807. The 
experiments must be varied and repeated , before they can be con- 
sidered as conclusive. But should they be found true , they will go 
a great way to induce us to believe , that potass , and even carbon , 
are compounds , and products of vegetable organization formed out 
of oxygen , hydrogen and light . 18 /Vzc/i Jowr. 15. 
PHYTOLOGISTS for a long time imagined, that vegeta- 
bles were nourished by certain juices, which they extracted rea- 
dy formed from the earth. Van Helmont in great measure re- 
futed this by his celebrated experiment. In a box containing 
100 lbs. of earth, and covered with lead, he planted a willow, 
weighing 50 lbs. This he watered with distilled water, and in 
five years it had acquired an addition to its weight of 119 lbs. 
3 oz. without any perceptible diminution of the earth. The ex- 
periments of Boyle with earth baked in an oven, and those of Du- 
ll am el and Bonnet with moss,* prove the same thing. 
Other natural philosophers have pursued the same inquiry? 
Tillet, in particular, made a number of experiments, to ascertain 
whether water and air were the only substances necessary for 
the growth of plants. He filled several pots with different ear* 
thy matters, some with old plaster, others with pure river sand, 
fragments of stone broken to powder, &c. ; buried them partly 
in the ground, to retain the moisture ; and sowed wheat in them. 
The wheat produced very fine ears ; and the grains, being sown, 
produced other fine plants. 
From the infant state of chemistry, at the time, however, none 
of the plants produced by means of air and water alone were ana- 
lysed. This indeed has since been done ; and it has been ad- 
vanced, that plants growing in such a manner as to have been 
nourished by water alone, did not furnish as much carbon as was 
* Mr. Procopius Densidoff of Moscow, sows seeds in moss, where they 
germinate, and then plants them in pots. In this way he loses very few seeds 
©f those that grow with most difficulty. JVote of Prof. Willmett . 
