Principles of scientific botany, or, Botany as an inductive science / by J.M. Schleiden ; translated by Edwin Lankester.

Date:
1849
Catalogue details

Licence: Public Domain Mark

Credit: Principles of scientific botany, or, Botany as an inductive science / by J.M. Schleiden ; translated by Edwin Lankester. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    19/646
    quantities of water in their tissues. In one hundred parts of Cerato' phyllum demersum ninety were found to be water, and ten solid matter. Carbonic acid is also widely diffused with water : it forms the principal source of nourishment for plants. It is found dissolved in the sap of plants : at night, in almost every plant; in the day, in ripe fruits, in aerial roots, &c. In consequence of the processes of respiration and combus- tion on the earth, and volcanic agency, the atmosphere contains an inex- haustible supply of carbonic acid for plants. Oxalic acid is constantly produced by the decomposition of the fore- going compounds, and is found apparently in all plants. It is found free in most succulent plants, as the Crassulacece, Ficoidece, Cactacece*, Sic.; also in the hair-glands of Cicer arietinum. b. Compounds zoith Hydrogen.—These are principally ammonia (NIP), hydrochloric, hydriodic, and hydrobromic acids. Ammonia is probably the source of nitrogen in all plants. It occurs free in the unassimilated sap, as in the spring sap of the birch and the grape vine, and perhaps also in the tissues of unnaturally succulent cultivated plants, as the beet. § 7. The foregoing oxides and acids unite together to form salts, some of which are found dissolved in the sap of plants, and others in the form of crystals. The most important are the alkalies in combination with the vegetable acids, or chlorine, bromine, and iodine; then, perhaps, those with sulphuric and phosphoric acids; whether any exist with carbonic acid, is doubtful: next come the earths, with vegetable acids, especially oxalic acid, then with sulphuric and phosphoric acids; and, lastly, the metals mostly in combinations not yet determined. The greater part of the salts are found in the living, vegetating, green parts of plants, as the leaves, &c.; the least, in the wood (Saussure). A certain quantity of these salts appears essential to the life of plants. Ammoniacal salts from the atmosphere appear to be the source of the nitrogen in plants. Fourcroy and Vauquelinf, long ago, proved that the greater part of the carbonates found in the ashes of plants were formed, during the burn- ing, from other salts of vegetable acids. They proved that almost all plants contain—1. acetate and malate of lime dissolved in the sap; 2. citrate and tartrate of lime, which either exist as a super salt or in a solid form; 3. oxalate of lime in a solid form. All these are found in the ashes of plants as carbonates; but these latter are not to be found if, before the burning, the plants are by turns treated with cold and boiling water and diluted muriatic acid. The salts of the alkalies are found dissolved in plants, but the insoluble earthy salts present themselves in a crystallised form in the cells. Of these, the oxalate of lime has been most accurately inves- * Liebig (Annal. xlvi. p. 77.) says the Cactacecc contain tartaric acid; but he is certainly wrong with regard to most Cactaccee. f De la Metherie, Journ. de Physique et de Chiin., tome lxviii. p. 429. (1809).