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peach-trees are no inappropriate representation of oxen grazing in large pastures; and the animalcules, in a drop of water, swim about with as much freedom as whales do in an ocean. They have all equal room in proportion to their bulk.
Nor power alone confessed in grandeur lies,
The discoveries of the microscope suggest to us this important truth, that our ideas of matter, magnitude, and minuteness, are merely comparative. They are taken from ourselves and the things around us, beyond which, if we endeavour to extend them, they become very indistinct. The beginnings and endings, excessive greatness or extreme littleness, of things, are to us all perplexity and confusion.
'Let a man,' says Mr. Addison', try to conceive the different bulk of an animal which is twenty, from another which is a hundred times. less than a mite; or to compare, in his thoughts, a length of a thousand diameters of the earth with that of a million; and he will quickly find that he has no different measures in his mind, adjusted to such extraordinary degrees of grandeur or minuteness. The understanding, indeed, opene
an infinite space on every side of us; but the Imagination, after a few faint efforts, is immediately at a stand, and finds itself swallowed up in the immensity of the void that surrounds it. Our Readers can pursue a particle of matter through an infinite variety of divisions; but the Fancy soon loses sight of it, and feels in itself a kind of chasm, that wants to be filled with matter of a more sensible bulk. We can neither widen nor contract the faculty to the dimensions of either extreme. The object is too big for our capacity, when we would comprehend the circumference of a world, and dwindles into nothing when we endeavour after the idea of an atom.'
But although the powers of the imagination be thus defective, the understanding is convinced by demonstration, and beholds this variety of wonders with astonishment and awe. Whether, with a Newton or a Herschel, we take the telescope, and compute the stupendous magnitude and velocity of a planet; or, with a Leewenhoeck or a Baker, survey, through a microscope, the structure and conformation of a mite; in each we are compelled to admire and adore the pervading wisdom and energy of the Creator:
In the Vast and the Minute
The unambiguous footsteps of the God,
A VIEW OF THE INSECT TRIBES
We wonder at a thousand insect forms,
INSECTS exhibit such an immense variety in figure, colour, and disposition of parts, that naturalists have found it necessary to arrange them into different tribes or families, distinguished from one another by certain peculiarities in the structure of their bodies.
The most general division of insects is derived from the circumstance of their having or wanting wings, and from the number and substances of which these instruments of motion are composed. They are distinguished from all other animals by many peculiarities of form. None of other classes have more legs than four. But most insects have six; and many of them have eight, ten, fourteen, sixteen, eighteen, and even a hundred legs. Beside the number of legs, insects are furnished with antenna, or feelers. These feelers, by which they grope and examine the substances they meet with, are composed of a great number of articulations or joints. Linné, and some other naturalists, maintain, that the uses of these feelers are totally unknown. But the slightest attention to the manner in which some insects employ their feelers will satisfy us of at least one use they derive from these organs. When a wingless insect is placed at the end of a twig, or in any situation where it meets
forward, elevates, depresses, and bends them from side to side, and will not advance further, lest it should fall. If a stick, or any other substance, be placed within reach of the feelers, the animal immediately applies them to this new object, examines whether it be sufficient to support the weight of its body, and instantly proceeds in its journey. Though most insects are provided with eyes, yet the lenses of which they consist are so small and convex, that they can see distinctly but at small distances, and, of course, must be very incompetent judges of the vicinity or remoteness of objects. To remedy this defect, they are provided with feelers, which are perpetually in motion while the animals walk. By the same instruments, they are enabled to walk with safety in the dark.
No other animals but the insect tribes have more than two eyes; but some of them have four, and others, as the spider and scorpion, have eight eyes. In a few insects, the eyes are smooth; in all the others, they are hemispherical, and consist of many thousand distinct lenses. The eyes are absolutely immoveable: but this defect is supplied by the vast number of lenses, which, from the diversity of their positions, are capable of viewing objects in every direction. By the smallness and convexity of these lenses, which produce the same effect as the object glass of a microscope, insects are enabled to see bodies that are too minute to be perceived by the human eye. Another peculiarity deserves also our notice. No animals, except a numerous tribe of four-winged insects, have more than two wings.
With regard to sex, quadrupeds, birds, and fishes, are distinguished into males and females. But the bee and the ant furnish examples of neuters, which are absolutely barren: and the earthworm, and several shell animals, are hermaphro
dite, each individual possessing the prolific powers of both male and female.
It is likewise remarkable, that all winged insects undergo three metamorphoses or changes of form the egg is discharged from the body of the female in the same manner as in other oviparous animals. By a wonderful instinct, these seemingly stupid creatures uniformly deposit their eggs on such animal or vegetable substances as furnish proper food for the worm or caterpillar, that is to be hatched by the heat of the sun. The worm or caterpillar is the first state. The bodies of caterpillars are soft and moist. They have no wings, and are totally deprived of the faculty of generation. After continuing for some time in this reptile state, they are transformed into a chrysalis, which is drier and harder than the caterpillar. The chrysales of some insects are naked, and those of others are covered with a silken web, spun by the animals before their change is completed. In this state, many of them lie motionless, and seemingly inanimate, during the whole winter. When the spring or summer heats return, they burst from their last prison, and, from vile reptiles, are transformed into beautiful flies. In this perfect state they are exceedingly active, fly about in quest of their mates, and, after propagating their species, the females deposit their eggs, and the same circleof animation and change perpetually goes round.
Poor insect! what a little day
And yet thou spread'st thy light wings gay,
Thou humm'st thy short and busy tune,
And careless, while 'tis burning noon,