446. The chemical or elementary principles of vegetables, are carbon, water, and air; or hydrogen (15), and oxygen (85), for the constituent parts of (100) water; and azote or nitrogen (72), and oxygen (28), as the constituent parts of (100) atmospheric air; and carbon.

Obs. 1.-Wood burnt in a close vessel till it has neither smell nor taste, will produce the basis of all vegetable matter called charcoal; or, when purified, called carbon, which is the most indestructible sustance in nature. The diamond approaches the nearest to pure carbon of any substance at present known.

2.It is found, that water is nothing but a composition of two airs or gases, one the inflammable or light gas called hydrogen, and the other the vital gas called oxygen; and water may be made by combining these; or, it may also be separated into these one hundred parts of water are composed of fifteen of hydrogen, and eighty-five of oxygen

3.-In like manner, the air or fluid in which we live, is found to be composed of 28 parts of oxygen, or pure vital air; and 72 parts of nitrogen, or azotic gas, but the due mixture of both, forms the salotary fluid or atinospheric air in which we breathe.

4.-I have explained the meaning of these easy teres in this place, in order to illustrate the beautiful provi sions of vegetables which follow. There is no mystery in them; and they may be understood now as well as when I treat of Chemistry.

447. Vegetables generate, or give out oxygen or vital air, in the light or sunshine, by a natural process of their own.

Air, which has been breathed by animals, deprived of its 28 parts of oxygen, and will ne longer sustain life.

In like manner, a body, while burning, de prives air of its 28 parts of oxygen, and the flame will go out.

An animal would die, or a flame go out, when put into air so deprived of its oxygen; but a vegetable will then thrive in it, and will restore it to its original power of sustaining animal life.

Obs. Hence, the oxygen of the whole atmosphere would, in due time, be consumed by the breathing of animals and by flame, but for this provision of nature. The leaves of vegetables give out oxygen in the day-time, and keep up the due proportion which is necessary to the support of animal life: the leaves of aquatic and herbaceous plants produce it, however, in the greatest quantity.

448. The saccharine and oily productions of vegetables are parts of their sap or juices; but the turpentine, the bitter, and the acid principles, are considered as the effect of preparation or secretion..

The green colour of vegetables arises from the oil they contain; the rays of the sun extracting the oxygen from the outer surface, and leaving the carbon and hydrogen, which are known to be the constituent parts of oil.

449. Healthy vegetables perspire water, by the under part of their leaves, equal to onethird of their weight every twenty-four hours; by which part they also give out oxygen.

450. Nor do they derive their substance in a principal degree from the matter of the soil in which they grow; but they are created by a vital principle of their own, out of air and water, and of the imperceptible matters combined with air and water, from which all their distinctions of smell, taste, and substance, are derived!

Hail, Source of Being! Universal Soul

Of heaven and earth! Essential Presence, hail!

By THEE, the various vegetative tribes,
Wrapt in a filmy net, and clad with leaves,
Draw the live ether, and imbibe the dew;
By THEE, disposed into congenial soils,
Stands each attractive plant, and sucks and swells
The juicy tide, a twining mass of tubes :
At Tay command, the vernal sun awakes
The torpid sap, detruded to the root
By wintry winds; that now in fluent dance,
And lively fermentation, mounting, spreads
All this innumerous colour'd scene of things.

THOMSON

451. Some plants exhibit signs of great sensibility, besides the effects in nearly all arising from the presence or absence of the rays of the sun these are the sensitive plant, whose leaves fold together on being touched by the band; and Venus's mouse-trap, which closes on any insect that goes into it, and stings it to death.

Obs. Throughout universal nature, a gradation of beings may be traced; and yet their particular differences elude the observation, like the various colours of the rainbow, blending and mixing with each other, Where vegetation ceases, or seems to cease, perception begins; and we trace some of the first rudiments, or sparks of it, in the actinia, or sea-anemone, the oyster, and the snail. The polypus ranks as the first of plants, and the last of animals; if its propagation, as some naturalists affirm, can be effected by cuttings, similar to the multiplication of plants-by slips and suckers. Then, it ascends through various gradations of beings, distinguished by more enlarged and active faculties, more perfect and more nunerous organs, to those creatures which approach to the nature of inan. We behold the distant resemblance of his sagacity in the elephant; of his social attachments in the bee and the beaver; and the rude traces of his form in the ourang-outang.