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Vegetation, or Botany

Vegetation is that evolution of germs, and that fixation of the elements, which serves as the food of loco-motive evolution in animal forms; for, though some animals devour one another, yet the devoured have been sustained by vegetation. Vegetable substances are the first term in the progression of substances, ending in the genera and species of all kinds of animals, and without vegetable preparation, mineral and earthly substances could not become animal substances: for though shells and bones are deposits of lime, yet the lime enters the animal after the preparation by vegetables. They are evolved by heat and light, and from air and water, in all situations where their food in the soil is not rendered intractible by metallic diffusion, and their varieties and universal distribution fit them for their end. The Linnæan system consists of twenty-four Classes, and twenty-six Orders, now divided into 3900 genera; into 50 or 60,000 species; and into an almost infinite number of varieties. The twenty-four Classes depend on the number of stamens, and the twenty-six Orders on the number of pistils.

The twenty-four CLASSES are called according to the number of Stamens :- 1. Monandria. 2. Diandria. 3. Triandria. 4. Tetandria. 5. Pentandria. 9. Enneandria. 10. Decandria. 11. Dodecandria. 12. Icosandria. 13. Polyandria. 17. Diadelphia. 18. Polyadelphia 19. Syngenesia. 20. Gynandria. 21. Monesia. 6. Hexandria. 7. Heptandria. 8. Octrandria. 14. Didynamia. 15. Tetradinamia. 16. Monadelphia. 22. Diœcia. 23. Polygamia. 24. Cryptogamia.

The ORDERS are as under, depending on the Pistils : 1. Monogynia. 10. Dodecaginia. 19. Monœcia. 1 2. Dygynia. 11. Polyginia. 20. Diœcia. 3. Trigynia. 12. Gymnospermia. 21. Triæcia. 4. Tetragynia. 13. Angiospermia. 22. Filices. 5. Pentagynia. 14. Siliculosa. 23. Musci. 6. Hexagynia. 15. Siliquosa. 24. Hepaticæ. 7. Octagynia. 16. Polygamia equalis. 25. Algæ. 8. Enneagynia. 17. Polygamia segregata. 26. Fungi. 18. Monogamia. 9. Decagynia.

Chemistry of Vegetation. -Gay Lussac and Thenard deduced three propositions, which they call laws of vegetable substances: First. That a vegetable substance is always acid, whenever the oxygen it contains is to the hydrogen in a greater proportion than in water. Second. That a vegetable substance is always resinous, or oily, or spirituous, whenever it contains oxygen in a smaller proportion to the hydrogen than in water.

Third. That a vegetable substance is neither acid nor resinous, but either saccharine or mucilaginous or analogous to woody fibre or starch, whenever the oxygen and hydrogen are in the proportions of water. The Chemistry of Vegetation consists in the decomposition of the aqueous solution of the soils; and re-combination of the elementary constituents in the membranes, fibres, and cellular and vascular tissues of the bark, wood, pith, or marrow. The fine membranes form mucilage, and in cells, chiefly hexagonal, pervades the whole plant. The chemical decompositions in plants are believed to be effected in the leaves, in which the sap is exposed to the action of the air. Vegetables are composed of carbon, oxygen, and some hydrogen, with nitrogen; and they mainly produce 1 gluten, farina, mucilage, oil, and sugar. Vegetables contain, in substance, acids, sugar, gum, mucus, jelly, starch, gluten, and five or six peculiar principles, as tannin, indigo, the bitter and narcotic principle, etc. They also yield oils, wax, resins, etc. In all about 34 several products. Vegetables yield nine several acids: the oxalic in rhubarb; the tartaric in tamarinds, grapes, and mulberries; the citric in oranges, lemons and onions, the malic in apples, cherries, etc.; the gallic in elm, oak, etc.; the benzoic in balsamic trees; the prussic in laurel-leaves, peach-blossoms, and bitter kernels; phosphoric in barley, oats, etc.

HYDROLOGY.

We live upon a globe whose surface is water and land. Pride leads us to give precedency to the latter, but figures tell us that the former is as 3 to 1, or 150 to 47, and nature shows us that soil and minerals are mere vehicles to the activity and agency of water. Nor is it only in a mechanical sense that water effects so many wonders; since, by weight; it is formed of 8 parts of oxygen, and I of hydrogen; and by volume of I of oxygen and 2 of hydrogen; and therefore it possesses within itself high powers of chemical union and decomposition. Some of the epigrammatic philosophers of Greece referred all things to water, and not without reason. It is the agent of all terrestrial activity, the universal percolator and solvent, the transferrer of atoms from body to body, of soils from place to place, and of land itself into the silent bosom of its own depths. Its tides and currents, its evaporations, its circuit as clouds, rain, and mists, and its subservience to heat and atmospheric pressure, render it the Universal Fertilizer. Then its decompositions yield the elements of hydrogen and oxygen, and so vary its mechanical products as even now to justify the conclusion of Thales and others, who had not witnessed, like us, the triumph of the steam-engine. We treat it as a subordinate of Geology, but in truth it is the absolute master, former, and secondary agent of the power of motion of everything terrestrial. It is that local display of the motions of the earth, as a planet, which elaborates every thing; and the waters contain far more organic beings than the land.

The Sea. The surface of the sea is estimated at 150 millions of square miles, taking the whole surface of the globe at 197 millions; and its greatest depth is supposed to be equal to that of the highest mountain, or four miles; but La Place thinks that the tides demand an average depth of three miles, therefore the sea contains 450 millions of cubic miles of the 258,000 millions in the whole globe. The Pacific Ocean covers 78 millions of square miles, the Atlantic 25 millions, the Indian Ocean 14 millions, the Southern Ocean to 30 degrees is 25 millions, the Northern Ocean 5 millions, the Mediterranean 1 million, the Black Sea 170,000 miles, the Baltic 175,000 miles, the North Sea 160,000 miles. The sea swarms with life like the land, in forms kindred to those on land, for the principles of the economy of all locomotive beings have the same general types. Water and mercury are the most perfect liquids; others are more or less viscous. The particles of liquids move and press equally in all directions; those of solids only downwards. They press on any surface, as the base by the distance to the upper surface of the fluid. The pressure is distinct from the weight of the mass. It is as the height whatever the base. A cone and cylinder of liquid of equal height have the same pressure. As every atom of a fluid is carried by the two motions toward the centre, so, when embanked, the whole attains a perfect level. It is believed that the freedom to move arises from the motions of the atoms among one another. All water, therefore, seeks the lowest level. The state of fluidity is preserved by the pressure of the atmosphere, the motion of the atoms being less than that of the atoms of air. Hence water expands into gas, either when the atmospheric pressure is removed, or when the atoms of water acquire more motion by access of heat. The earth would vibrate, owing to irregular forms of its sold granitic nucleus, but for the mobile waters, which preserve the balance of its sides and parts, and accommodate themselves to any unequal impulses of rotation. But as the Americas run from north to south, it may be suspected that they rotate a small fractional part above the general distance from the centre, and are colder. Between the Tropics the temperature of the sea is from 77° to 84°. It diminishes to 45.5° at 1000 fathoms depth. But, in the Arctic Sea, the temperature rises from 8° to 10º at 700 fathoms, and 6º at 200 fathoms. The sea is bluish green, and the Arctic Sea is ultramarine, and transparent blue to olive-green or opaque, in stripes caused by animalculæ and medusæ in countless myriads. In the Gulf of Guinea it is white, and round the Maldives black. In other places it is red and purple. The solar rays penetrate 2 or 300 feet, and objects may be seen in Arctic and West Indian seas at 150 feet. The luminosity of the ocean arises entirely from small insects, whose figures have recently been exactly determined by observations with the microscope.