Experiments and observations on the vegetation of plants : which shew that the common opinion of the amelioration of the atmosphere by vegetation in solar light, is ill founded / by James Woodhouse.

  • Woodhouse, James, 1770-1809.
Date:
[1802?]
Catalogue details

Licence: Public Domain Mark

Credit: Experiments and observations on the vegetation of plants : which shew that the common opinion of the amelioration of the atmosphere by vegetation in solar light, is ill founded / by James Woodhouse. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    . nc air. ON THE VEGETATION OK PLANTS. whenever they appear to afford oxigenous gas it is by devour- ing the coal of carbonic acid gas for food, and leaving its ox- igen in the form of pure air. I have the honour to be, Dear Sir, With the greateft refpecr, Your moft obedient, And very humble fervant, JAMES WOODHOUSE. Firft. Of tlie Ejfe&s p/oduced by the Germination of Seeds in atmofpherical Air. irmiiution of On the 3d of June, twelve feeds of zea maiz were planted Is in atmo- jn earth, and confined over water in a glafs veffel, in feventy ounce meafures of atmofpherical air of the purity of 100, and often expofed to the light of the fun. On the 12th, the corn had vegetated, and was from two to five inches high. The air being examined at this time, by throwing up one meafura of it, over lime water, in an eudiometer, gave ^fa parts of car- bonic acid air. Another meafure, after being freed from the fixed air, and mixed with an equal meafure of nitrous air, pro- duced an abforption of T3?>V On the 19th, the corn having grown confiderably, and the air being tried again, no carbonic acid gas appeared, and the purity was the lame as at firft. On the 23d, the plants died, and the airs were found to confift of -j-5-5 fixed, and TVo azotic gas. Similar experiments were made with the feeds of apium pe- trofelinum, laftuca fativa, cucurbita citrullus, phafeolus fativus, fifymbrium, and raphanus fativus, and with the fame refult. ie air loft oxi- The atmofpherical air, in thefe experiments, appears to be. n by uniting rec}uced in purity, by its oxigen uniting to the coal of the coty- Bbhte^r Iedons of the feed, or to that of fome animal or vegetable mat- ire pure; and ter contained in the earth in which the feeds are planted, or to Kiwi that of fome decayed PorLion of the livinsIeaves- bed.' Ingenhouz, Humbold, and Thomion, have obferved, that ,e effefl of - .. j^ the property of abforbing oxigen ; but as it cannot y. mould on r r j moft probably be proved that any pure earth, or mixture ot earths, render at- m its carbon. mofpherical air impure, it is certainly more philol'ophical to afcribe the impurity of the air to the formation of the carbonic acid, the bafe of which generally extfts in all foils.