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THOMSON.

Swarming, they pour : of all the varied hues,
Their beauty-beaming parent can disclose.
Ten thousand forms, ten thousand different tribes
People the blaze! To sunny waters some,
By fatal instinct fly: where on the pool,
They, sportive wheel; or, sailing down the stream
Are snatch'd immediate by the quick-eyed trout,
Or darting salmon. Through the greenwood glade
Some love to stray : there lodg’d, amus'd, and fed,
In the fresh leaf. Luxurious, others make
The meads their choice, and visit every flower,
And every latent herb: for the sweet task,
To propagate their kinds, and where to wrap,
In what soft beds their young, yet undisclos’d,
Employs their terder care. Some to the house,
The fold, and dairy, hungry, bend their flight:
Sip round the pail, or taste the curdling cheese
Oft, inadvertent, from the milky stream
They meet their fate : or, weltering in the bowl,
With powerless wings, around them wrapt, expire.

511. Animalcules are shaped like fish, reptiles, eels, stars, hexagons, triangles, ovals, and circles; they have horns, probosces, &c. and although the eyes of many species are not discernible, yet they move about with inconceivable relative velocity in the fluids they inhabit, without interfering with each other.

512. Hunter divided all animated nature into single and complicated animals. The single, are those which possess only feeling or the powers of muscular contraction, and the power of absorbing food, as chalk absorbs moisture, and appropriating it to nourishment.

The Hydatid, found in sheep, consists only of a bag filled with water, and has no appearance of animal powers; but, when excited or pricked, contracts and shews its irratibility; while this vital power is supported by the nourishment which it receives through its coat.

513. From such simple animals, we ascend, through all the degrees, up to the complicated and combined powers of body and mind, in Man!

The links are kept up, by the addition of muscles, for additional motions; by other senses, for hearing, seeing, &c. and by various degrees of irratibility in those senses.

The blood for renovation circulates through the lungs; and for action through the muscles of the heart; secretions take place by the various glands; the contraction of the muscles moves the bones; the nerves convey the effect of the mental secretions to the brain; and there produce the inscrutable powers of sensation, will, and judgment.

514. Although animals, in general, are sufficiently distinct from vegetables, yet the gradations of nature are so minute, that many animals are but slightly removed from vegetables, having not more than one or two senses; and, as in some shell-fish, have not even the power of loco-motion.

Between these and man, there is a regular succession of that cunning and sagacity which are necessary to preserve and sustain life; yet between man and most other animals, there is, in mental capacity, as great'a difference as between some of those and vegetables.

Far as creation's ample range extends,
The scale of sensual, mental powers, ascende:
Mark, how it mounts to man's imperial race,
From the green myriads in the peopled grass :
What modes of sight, betwixt each wide extreme,
'The mole's din curtain, and the lynx's beam;
Of smell, the headlong lioness between,
And bound sagacious, on the tainted green:
Of hearing, from the life that fills the floed,
To that which warbles thro' the vernal wood!
The spider's touch, how exquisitely fine!
Feels at each thread, and lives along the line :
In the nice hee, what sense so subtly true!
From poisonous herbs extracts the healing dew:
How instinct varies in the grovelling swine,
Compar'd, half-reasoning elephant, with thine !
"Twixt that, and reason, what a nice barrier!
For ever separate, -yet for ever near!

TOTE.

Seven remarkable specimens of Animated Nature.,

AN ELEPHANT.

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Obs.-In Art. 127 and 128, are described the transformations of insects, from the egg to the worm-the worm to the chrysalis--and the chrysalis to the butterfly.

The following cut represents those four states in the common catterpillar.

THE EGGS, THE CATERPILLAR, CHRYSALIS,

AND BUTTERFLY.

[graphic]

XXI. Chemistry 515. By Chemistry we ascertain the ingredients, component parts, or first principles of which all kinds of matter are composed.

DEFINITIONS. 1. Decomposition implies the separation of the elementary substances of which any compound substance is formed.

2. Pulverisation signifies the mere mechanical separation of bodies into smaller ones, without being decomposed into its elementary ingredients.

3. Chemical affinity affords proof that atoms are compounded in different forms, which coalesce and dovetail together with more or less facility.

4. The sensible atoms appear attracted or repelled accordingly as they, or those of the media in which they are placed, are more or less mutually affected.

5. The substance which decomposes another, is called a chemical test or re-agent.

6. If a salt be dissolved in water, it is said to be in solution, and the water is oalled the menstruum.

7. When water will dissolve no more of any substance, the water is said to be saturated.

8. If we would extract the salt, we must evaporate the water by heat, with a still, a retort or alembic; and if the va. por from either of these pass through a spiral tube or worm,

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