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INTRODUCTION.

If a person whose life, from infancy to manhood, had been passed in some volcanic island, where scarcely a lichen covered the rock, should be suddenly removed into a region of luxuriant vegetation, his wonder and admiration could not fail to be excited by the scene around him. The return of spring would indeed appear to him as an “annual miracle,” and he would probably inquire earnestly into the causes by which the vernal leaves and flowers were produced. Habit has so familiarized us with these beautiful objects, that many of us forget to bestow a thought upon them; and we eat our bread, wear our linen, or sail the ocean in our majestic vessels, without a recollection of the growth of the corn, the flax, or the oak.

In this, as in many other matters, King Solomon has set us a wiser example. Monarch, statesman, and philosopher as he was, he nevertheless found leisure to make himself acquainted with every plant,

." " from the cedar of Lebanon to the hyssop on the wall;" and "

a greater than Solomon" vindicated the claim of this exquisite part of the creation to be studied and admired, when he declared that the Monarch of Israel,“ in all his glory," was not arrayed like one of the lilies of the field; while at the same time he instructed us how to draw from the study its most consoling and important inference, that “if God so clothe the grass,” his fostering love will assuredly be bestowed in full measure on us, his rational creatures.

There is one point of view from which the ac

quaintance with any of the works of creation assumes its highest moral aspect, God is Truth ; the one only source from which no error ever flows; and whenever we have arrived at the undoubted knowledge of any facts in nature, we have made a fresh approach to truth, and to the “ Fountain of Truth.'

Let the subject of inquiry be what it may, this assertion will be found to hold good. What God has not disdained to make, we may surely think it time well bestowed to examine, and coming to that examination in a right spirit, we may indeed find “ tongues in trees,” and even in what man, in his insolence, has called the meanest weeds.

In one of the former “Small Books," some insight has been afforded into the wonderful chemistry perpetually going in the vegetable as well as in the animal department of the great laboratory of nature. It is the object of the present little treatise to give a general idea of the structure, nourishment, and reproduction of the plants themselves,-of Vegetable Physiology in short;--and although the compass of this work is too small to admit of much technical detail, it is hoped that enough information may be conveyed to increase the interest with which its readers will henceforth view the vegetable world around them, and to excite a wish, in those who may have leisure, to pursue the subject at some future day.

The following Treatise makes no pretension to originality, being a compilation chiefly from the works of M. de Candolle, Alphonse de Candolle, sometimes almost literally translated,-Professor Lindley, &c., carefully put together with a view to afford an enlarged idea of the general nature of the subject, and to justify the assertion of the first named physiologist, that from the apparently humble func

tions of vegetable life, we may raise our thoughts to the contemplation of the universal order that exists in the natural world.*

Let us now return to our imaginary personage, who has inhabited a volcanic island destitute of vegetation, and has been supplied with food for both man and beast from elsewhere. He has seen rocks, and locomotive, sentient beings, and nothing else. He quits his island, and lo! the earth is covered with grass, and trees, and flowers, and fruit, whose use soon becomes apparent from the myriads of living creatures which find their food there,—but what is this new appearance? Is it the rock shooting up into crystals under the influence of the sun and rain, as salt crystalizes from sea water ? But the rock, when broken, retains its characteristic forms and substance unchanged : our islander pulls a herb, or cuts a branch, he finds moisture exuding from it, like blood from the flesh of an animal ; and the uprooted, or cut portion withers and decays. It has, then, in common with the animal, some interior mechanism for the transmission of fluids, and some principle by which this mechanism is regulated: for though not one particle of the severed portion be injured by the cutting off from the tree, it can exist no longer than while it forms part of an individual; and the mechanism which nourished it is useless when removed from the influence of that individual principle : this principle is something distinct from mere tubes and fibres, and its operation appears closely to resemble what is called life in animals. Our inquirer therefore will soon resolve that the vegetable

* To the recent works of Dr. Carpenter on Animal and Vegetable Physiology, and to Professor Henslowe’s “ Principles of Descriptive and Physiological Botany,” the writer thankfully acknowledges much obligation.

is more nearly allied to the animal than to the rock, and he will ask himself again, what is the difference between the rooted animal and the rooted vegetable? Is not the vegetable, the lowest grade of living beings, akin to the coral and other such tribes of animal plants? He will find an organism, resembling in many cases the lower kind of animals, vessels transmitting moisture upwards, and carrying it downwards, -while others are charged with the supply of air : and the fibres and cellular tissue are formed from the circulating liquid, as the muscle from the blood. The substance of the vegetable, when examined chemically, affords fibrine and albumen, the components of blood : its ultimate elements are mainly the same as those of animals, i. e., oxygen, carbon, hydrogen, and nitrogen, the residue of ashes alone affording a small portion of other elements, chiefly alkalies. Is there any real difference between the non-locomotive animal and the non-locomotive plant?

For a long time the answer to this question was in the negative, and the world heard of the links of the chain all through nature, the vegetable, the animal, and the intellectual kingdoms blending like prismatic colors, so intimately, that it was impossible to mark the boundary. But our inquirer, with the aid of modern research, will not allow himself to be influenced by theories, however plausible; he will expect to have the means of proof ere he acquiesces in any scientific view, and he will soon perceive one marked difference between the plant and the animal; for the root of the former is furnished with organs for the reception and assimilation of nourishment, while that of the latter is a simple means of attachment to one spot; and the nourishment, instead of being derived from the rock on which it is fixed,

floats to the mouth or mouths of the rooted zoophyte, and is of a totally different nature. The plant feasts on unorganized matter, imbibed in a fluid state by the roots and leaves, and never collected into any common receptacle; the animal requires organized matter in a solid state, which is received by a mouth into a stomach, where it is reduced to a semifluid mass; and not till then does the process of assimilation begin. The distinction is broad and clear, and our inquirer will now go on to admire the beautiful mechanism by which the rock, disintegrated by the action of the air, and dissolved by the rain, passes into the vessels of the plant, and there becomes organized, so as to fit it for the stomach of the animal, where it undergoes still farther changes; and finally, produces an organ fitted for the use of a higher order of beings ; for it cannot now be doubted that the brain, which is the finest product of animal organization, never is fully called into action till it becomes part of an individual of a yet higher grade. The potass, &c., of the volcanic rock is in great measure inert till it passes into the absorbent vessels of the plant, and the plant is of no use in creation farther than it supplies the nourishment for sentient organism, and the use of the sentient organism, finally, is only demonstrated when a fresh agent is introduced, and the intellectual Will crowns the fair work of Creation.

To an observer such as is above described, that link of the chain which connects man with the rock will have a deeper interest than the mere examination of any mechanism, however curious, could inspire: for the announcement that man is formed from the dust of the earth has a deep truth in it which modern science alone can fully appreciate. It is from this dust, that, after the various chemical com

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