see nothing, and would be blinded by the strong refraction of the rays of light, though they have two well-formed eyes, if their chrystalline humour was not spherical, by which they are enabled the better to collect the rays of light. They have no eye-lids, and they cannot draw back their eyes; but their cornea, which is almost as hard as horn, preserves them from all danger. The mole was formerly supposed to be blind; but it is now discovered that it has extremely small black eyes, not larger than a pin's head. As this animal is almost always under ground, its eyes are defended from injury by being thus small, deep in the head, and covered with hair. The eyes of snails are placed at the extremities of their horns, which they can draw within their heads, or push out to discover distant objects. In some animals whose head and eyes are fixed and incapable of motion, this defect is compensated either by their superior number of eyes, or in some other way. The spider has four, six, and sometimes eight eyes, all placed in the front of a small round head without a neck; they are transparent and sparkling as diamonds. According to the mode of life and different necessities of certain species of spiders, their eyes are differently distributed in their head, that their sight may be extended to all sides, and that without moving their head they may discover the flies which they wish to ensnare. The cameleon, a species of lizard, has the singular property of moving one of its eyes whilst the other remains motionless; of turning one upward whilst the other looks down upon the ground; and of seeing at the same time both what is before it, and what behind. We observe the same faculty in some birds, and in hares and rabbits, whose eyes are convex; this peculiar property preserves them from many dangers, and enables them more easily to discover their food.

All these examples, and a much greater number might be given, evidently manifest the tender cares of Providence for the preservation of the most necessary organs. He has communicated the blessing of light to his creatures in different ways; and we are struck with admiration, when we consider the wonderful art displayed, and the precautions taken to preserve the possession of this precious organ, and to defend it from the dangers to which it is exposed. The situation of the eyes, their arrangement, number, and figure,

in all animals could not have been differently disposed without the greatest inconvenience being felt. It is not merely for ornament and beauty, but for the benefit and advantage of the animals, that the Creator has made so much diversity in the structure and position of their eyes. Let the foregoing observations teach us to acknowledge and to celebrate the wisdom of God in all things; and seriously to consider the ends which he has proposed in the creation, that we may more and more magnify and exalt his power and goodness.

SEPTEMBER X.

Fish.

UNLESS we had seen fish, it would have been impossible to believe that such creatures existed. If a naturalist, who was only acquainted with land animals, were told that a species of creatures inhabited water, so formed, that they could live, move, and propagate, and fulfil all the animal functions in that element, would he not treat such information as unworthy of belief, and conclude from what happens to our own bodies when immersed in water, that it would be impossible for any animal to live and breathe long in a watery medium?

The way in which fish live, their structure, their motion, and propagation are very curious, and afford fresh proofs of the wisdom and power of God. That animals may live in water it is necessary that their bodies be very differently constructed from those which live only upon land. And this peculiarity we find when we examine the exterior and interior structure of fish. Why have most fish a slender thin body, flattened on the sides, and pointed towards the head, but to enable them to swim, and more easily cut through the water? Why are they covered with scales, if not that their bodies may be defended from the pressure of the water? Why are many fish, particularly those which are destitute of scales, enveloped with a smooth oily covering, but to preserve them from injury, and to keep them warm? Their bones are peculiarly light and flexible; their eyes are deep in their head, and their chrystalline humour is spherical, that they may be secured from injury, and VOL. II.

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more able to concentrate the rays of light. Their fins are their only limbs, and by them they perform their different motions. By means of their tail fin, they move forward their back fin directs the motion of their bodies; their breast fin enables them to rise, and their belly fin preserves their balance. The gills are their organs of respiration; they are placed behind their head; and there are four of them on each side; of which the uppermost are the largest. They continually take in water by their mouth, which is their inspiration, and evacuate it through the gills, which is their expiration. The blood which proceeds from the heart, and which passes through the veins of the gills, does not return through the lungs to the heart, as in terrestrial animals, but is directly distributed to every part of the body. The organ most essential to fish in swimming is the air-bladder enclosed in their belly, and communicating with their stomach. By means of this bladder, they can make their body more or less heavy; when it is inflated they become lighter, rise, and can swim near the surface of the water; but when it is contracted, and the air is compressed, the body becomes heavier, and sinks in the water. If the bladder is pricked with a pin, the fish immediately falls to the bottom, and cannot again rise to the surface.

The immense number of fish, and their great variety of shape and size, also merit our attention. In the waters of Germany only there are more than four hundred different species of fish, and how numerous must be the individuals of each species! Their figure also is much varied. We see among fish the greatest as well as the smallest animals. Some are long and fine as a thread; others short and broad; others are flat, round, triangular, &c. and some are armed with a horn; others with a species of sword; and others with a kind of saw. Some have nostrils through which they evacuate the superfluous water they have swallowed. We have in all this abundant cause to admire the power and wisdom of the Creator, so eminently displayed in the formation of these animals, and to be grateful for his goodness in giving them all for our use.

SEPTEMBER XI.

Of the Propagation of Animals.

IT was once supposed that vermin, insects, and even some quadrupeds, were generated from putrefaction, without the interposition of other animals of the same species; but this opinion, so contrary to reason, is refuted by the most incontestable experiments. It is now generally understood that all animals are capable of producing others, and that this propagation is generally effected in two ways; by eggs, and by producing the young ones alive. All animals that give milk, or of the class of mammalia, are viviparous. All birds are oviparous; but their eggs, before they are capable of producing young creatures, must be impregnated by the male. In most animals it is necessary for the male and female to unite together; fish only seem to be an exception to this rule. They have not been known to couple, but the male is supposed to impregnate the eggs after they have been spawned.

Fish are the most prolific of all animals; their multiplication is astonishingly great. It has been ascertained that the pike lays three hundred thousand eggs, the carp above two hundred thousand, and the mackarel near half a million. The eel is viviparous. Most amphibious animals propagate their species like others, except that some of them resemble fish in this particular. Some are viviparous, and others oviparous; the latter however do not hatch their eggs, but leave them to the warmth of the air, or water; and others deposit them in dunghills.

Worms are both viviparous and oviparous; most of them, if not all, are hermaphrodites, partaking of the nature of both sexes, with the power of self-impregnation. The dis tinction of sexes is very evident in most insects; though in some no sex can be observed, and others seem to combine both sexes in one body. Insects are generally oviparous; though some are viviparous. The eggs of the former are hatched by the warmth of the air. The insect called the leaf-louse, or blight, is viviparous; an insect of this species taken at the time of its birth, separated from all intercourse with insects of the same species, and shut up perfectly alone, will nevertheless produce young ones. This takes place in the following manner: In spring, and during sum

mer, the females of this class of insects bring forth their young without previous union with the male; they are then viviparous. A single one will produce a hundred more in less than three weeks. All that are born in this seasonare females: the males are produced in autumn; at which time they couple, and the females lay eggs, which are hatched in spring. Thus one junction of the male and female produces several generations, the individuals of which are impregnated in their mother's eggs also.

When we reflect on this variety in the propagation of animals, we must be convinced of the power and wisdom manifested in an extraordinary degree. The instinct which leads the two sexes to unite together is truly admirable, and is a natural propensity, not produced by any external or adventitious circumstances. Most animals have a precise time for bringing forth their young, and every thing that is known with respect to this part of the animal economy displays an equal wisdom with the rest of nature's works; and we have great reason to be thankful that the different species of animals are preserved by means of that instinct, which induces them at certain periods to unite together for the preservation and continuance of their race.

SEPTEMBER XII.

Influence of the Moon upon the Human Body. FORMERLY certain influences were ascribed to the moon, tending to nourish superstition and occasion idle fears. The gardener would not plant till he had made observations on the moon, and the husbandman would not sow till he was assured of the happy influence of this planet. Those who were sick paid a strict attention to the variations of the moon, and even physicians regarded their influence as an object worthy of notice. As knowledge became more generally diffused, these prejudices began to disappear; and the influence of the moon is no longer considered so powerful and universal an agent in nature as was formerly imagined. The present age is less superstitious than the last; and it is the duty of every man to use all his exertions in separating truth from error, and to rescue his fellow-creatures from the despotic sway of blind superstition. With regard