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ination: he must be conversant with all that is awfully vast or elegantly little. The plants of the garden, the animals of the wood, the minerals of the earth, and meteors of the sky, must all concur to store his mind with inexhaustible variety: for every idea is useful for the enforcement or decoration of moral or religious truth; and he, who knows most, will have most power of diversifying his scenes, and of gratifying his reader with remote allusions and unexpected instruction.'

'All the appearances of nature I was therefore careful to study, and every country which I have surveyed, has contributed something to my poetical powers.'

'In so wide a survey,' said the prince, you must surely have left much unobserved. I have lived, till now, within the circuit of these mountains, and yet cannot walk abroad without the sight of something which I had never beheld before, or never heeded.'

'The business of a poet,' said Imlac, 'is to examine, not the individual, but the species; to remark general properties and large appearances; he does not number the streaks of the tulip, or describe the different shades in the verdure of the forest. He is to exhibit in his portraits of nature such prominent and striking features, as recall the original to every mind; and must neglect the minuter discriminations, which one may have remarked, and another have neglected, for those characteristics which are alike obvious to vigilance and carelessness.

'But the knowledge of nature is only half the task of a poet; he must be acquainted likewise with all the modes of life. His character requires that he estimate the happiness and misery of every condition; observe the power of all the passions in all their combinations, and trace the changes of the human mind, as they are modified by various institutions and accidental influences of climate or custom, from the sprightliness of infancy to the despondence of decrepitude.

'He must divest himself of the prejudices of his age or country; he must consider right and wrong in their abstracted and invariable state; he must disregard present laws and opinions, and rise to general and transcendental truths, which will always be the same: he must therefore content himself with the slow progress of his name; contemn the applause of his own time, and commit his claims to the justice of posterity. He must write as the interprete of nature, and the legislator of mankind, and consider him

self as presiding over the thoughts and manners of future generations; as a being superior to time and place.

'His labor is not yet at an end: he must know many languages and many sciences; and, that his style may be worthy of his thoughts, must, by incessant practice, familiarize to himself every delicacy of speech and grace of harmony.'

LESSON LXXVII.

The Three Kingdoms of Nature.-BINGLEY.

NATURAL objects have been in general arranged, for the purpose of classification, under the three grand divisions of minerals, vegetables, and animals. Minerals are natural bodies destitute of organization and life; vegetables or plants are natural bodies endowed with organization and life, but destitute of voluntary motion and sense; and animals are natural bodies which possess organization, life, sensation, and voluntary motion.

1. MINERALS.

If we penetrate beneath the surface of the earth, we discover there a remarkable arrangement. Instead of a generally uniform appearance, as we see on the surface, we pass through divers substances, as clay, gravel, sand, &c., deposited in beds or strata of various thickness, from a few inches to a great many feet. These lie, for the most part, nearly horizontal; but in some instances, particularly in mountainous countries, they take different degrees of inclination; and in places where the country consists of gentlysloping hills and vales, the beds have a waving or bending form.

These strata, as deep as the curiosity or the necessities of mankind have induced them to explore, satisfactorily demonstrate the wisdom which has been displayed, in the arrangement of materials requisite for the use of men and animals. The first layer is frequently a rich black mould, formed almost wholly of animal and vegetable remains; this yields sustenance to the vegetable productions, and thereby becomes the actual, though not the immediate support of the whole animal creation.

Beneath this is often found a thick bed of clay, that furnishes to man a substance of which to make bricks, tiles, various kinds of pottery, and innumerable other articles for the comfort of social life. Next are deposited vast beds of gravel, that are of use in numerous points of view. Underneath this are the infinitely-varying strata of sand-stone, lime-stone, &c., which not only serve for the construction of buildings, and for other important purposes, but also frequently surround mines, which contain the valuable metals.

Beneath a slaty stratum are usually discovered those immense beds of coal so requisite for the comfort, and, in some situations, even for the existence of man. These strata, it is true, are not always found together, nor are they always discovered in the same order; but the statement will suffice to show the general nature of their arrangement.

The most simple and natural division of minerals is into four classes,-stones, salts, combustibles, and metals. Stones are subdivided into earthy and saline; and metals into malleable and brittle.

2. VEGETABLES.

The principal parts of plants are the root; the herb, tree, or plant itself; and the fructification, or flower and fruit.

The roots of plants and trees, having nothing pleasing to the eye, the Creator has, for the most part, hidden from the view; they are nevertheless of great importance in the vegetable economy; they are furnished with a set of vessels by means of which they draw moisture from the earth;_ and they fix the plant in the spot it is designed to occupy. They are of various kinds, and have different periods of duration; and they are frequently observed to compensate, in an extraordinary manner, for local inconveniences,—changing their direction, for instance, when they meet with a stone; turning aside from barren into fertile ground; and, when stationed on the rocky edge of a deep ditch, creeping down one side and ascending the other, so as to place themselves in richer soil.

The plant itself consists of a variety of layers and vessels curiously arranged, and adapted for performing all the functions of vegetable life. First of all is the cuticle, or bark, investing every part of a living plant, and varying in texture from the delicate covering of a flower to the rough coating of a pearly aloe. It is furnished in many parts with pores, through which air and light are admitted; and it is

not only essential to plants in general, but also produces an elegant effect.

To the cuticle succeeds a green substance, called the cellular integument; then comes the bark, the innermost layer of which is called the liber; and, lastly, the wood, which sometimes contains within it the pith, supposed to be a reservoir of moisture or vital energy.

A variety of concentric circles beautifully diversify the surface of the wood, each of them showing the growth of a year. The wood itself consists of two parts,-the internal or true wood, which is hard and darkly-colored; and the outer, or alburnum, which is different in appearance, and not yet completely hardened.

The sap-vessels ascend from the points of the roots, through the superficial alburnum, become spiral and coated a little below the leaves, and enter them in a central arrangement round the pith. The fluid destined to nourish a plant, being absorbed in the root, becomes sap, and is carried up by these vessels into the leaves, where it undergoes a wonderful chemical change, and is brought back, through another set of vessels, down the leaf-stalks into the liber, where it is supposed to deposit the principal secretions of the tree.

Thus, to the bark of the oak, a tanning principle is communicated; to the Peruvian bark, what has been found so beneficial in fevers;-to the cinnamon, its grateful aromatic taste; to the sandal-wood, its never-dying fragrance, so beautifully noticed in an Aga couplet, which pronounces the duty of a good man to consist, not only in pardoning, but also in benefiting his enemies, as the sandal-tree, at the moment of its overthrow, sheds the sweetest perfume on the axe that fells it.

The parts of fructification are, the calyx, corolla, stamens, pistils, seed-vessel, seeds, and receptacle. The calyx, or flower-cup, is the green part which is situated immediately beneath the blossom; the corolla, or blossom, is that colored part of every flower, on which its beauty principally depends, and the leaves that compose it are denominated petals. The stamens and pistils are in the centre of the flower, and are the organs on which the fructification and reproduction of the plant more particularly depend. The former surround the latter, and consist each of a filament or thread, and an anther or summit; which last, when ripe, contains a fine powder called pollen.

At the foot of the pistil is situated the germen; this, when grown to maturity, has the name of pericarp, or seed-vessel, and is that part of the fructification which contains the seeds -whether it be a capsule as in the poppy, a nut as in the filbert, a berry as in the gooseberry, a pod as in the pea, or a cone as in the fir-tree. The seed is so well known as to require no description; and the receptacle is the base which connects all the parts of fructification together, and on which they are seated; as, for example, the eatable part of the artichoke.

3. ANIMALS.

The objects comprehended within the animal kingdom are divided into six classes,-Mammalia, or mammiferous animals; Birds; Amphibia, or amphibious animals; Fishes; Insects; and Worms.

The class Mammalia consists of such animals as produce living offspring, and nourish their young ones with milk supplied from their bodies; and it comprises quadrupeds, bats, seals, and whales.

The class Birds comprises all such animals as have their bodies clad with feathers.

Under the third class, or Amphibia, are arranged such animals as have a cold, and generally naked body, a lurid color, and nauseous smell. They respire chiefly by lungs, but they have the power of suspending respiration for a long time; they are extremely tenacious of life, and can repair certain parts of their bodies which have been lost; they are also able to endure hunger, sometimes even for months, without injury.

Fishes constitute the fourth class of animals; they are all inhabitants of the water, in which they move by certain organs called fins; they breathe by gills.

Insects are so denominated, from the greater number of them having a separation in the middle of their bodies, by which they are, as it were, cut into two parts. They have in general six or more legs, besides wings, and antennæ, or instruments of touch; and they nearly all go through certain great changes at different periods of their existence.

The sixth and last class of animals consists of Worms or Vermes, which are slow of motion, and have soft and fleshy bodies. These animals are principally distinguished from those of the other classes, by having tentacula or feelers.

Such are the three kingdoms of nature, and their principal divisions, according to the system of Linnæus, a distinguish

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