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there is a most curious and beautiful correspondence between this juice in the stomach of different animals and the other parts of their bodies, connected with the important operations of eating and digesting their food. The use of the juice is plainly to convert what they eat into a fluid, from which, by various other processes, all their parts, blood, bones, muscles, &c., are afterwards formed. But the food is first of all to be obtained, and then prepared by bruising, for the action of the juice. Now, birds of prey have instruments, their claws and beaks, for tearing and devouring their food, (that is, animals of various kinds,) but those instruments are useless for picking up and crushing seeds; accordingly they have a gastric juice which dissolves the animals they eat; while birds which have only a beak fit for pecking, and eating seeds, have a juice that dissolves seeds, and not flesh. Nay, more, it is found that the seeds must be bruised before the juice will dissolve them: this you find by trying the experiment in a vessel with the juice; and accordingly the birds have a gizzard, and animals which graze have flat teeth, which grind and bruise their food, before the gastric juice is to act upon it.

FEET OF THE CAMEL, HORSE, AND REIN-DEER.

The fitness of different animals, by their bodily structure, to the circumstances in which they are found, presents an endless subject of curious inquiry and pleasing contemplation. Thus, the Camel, which lives in sandy deserts, has broad spreading hoofs to support him on the loose soil; and an apparatus in his body by which water is kept for many days, to be used when no moisture can be had. As this would be useless in the neighbourhood of streams or wells, and as it would be equally so in the desert, where no water is to be found, there can be no doubt that it is intended to assist in journeying across the sands from one watered spot to another. There is a singular and beautiful provision made in this animal's foot, for enabling it to sustain the fatigue of journeys under the pressure of its great weight. Besides the yielding of the bones and ligaments, or bindings, which gives elasticity to the foot of the deer and other animals, there is in the camel's foot, between the horny sole and the bones, a cushion, like a ball, of soft matter, almost fluid, but in which

there is a mass of threads extremely elastic, interwoven with the pulpy substance. The cushion thus easily changes its shape when pressed, yet it has such an elastic spring, that the bones of the foot press on it uninjured by the heavy body which they support, and this huge animal steps as softly as a cat.

Nor need we flee to the desert in order to witness an example of skilful structure: the limbs of the Horse display it strikingly. The bones of the foot are not placed directly under the weight; if they were in an upright position, they would make a firm pillar, and every motion would cause a shock. They are placed slanting or oblique, and tied together by an elastic binding on their lower surfaces, so as to form springs as exact as those which we make of leather and steel for carriages. Then the flatness of the hoof, which stretches out on each side, and the frog coming down in the middle between the quarters, adds greatly to the elasticity of the machine. Ignorant of this, ill-informed farriers nail the shoe in such a manner as to fix the quarters, and cause permanent contraction of the bones, ligaments, and hoof-so that the elasticity is destroyed; every step is a shock; inflammation and lameness ensue.

The Rein-deer inhabits a country covered with snow the greater part of the year. Observe how admirably its hoof is formed for going over that cold and light substance, without sinking in it or being frozen. The under side is covered entirely with hair of a warm and close texture; and the hoof, altogether, is very broad, acting exactly like the snow-shoes which men have constructed for giving them a larger space to stand on than their feet, and thus avoid sinking. Moreover, the deer spreads the hoof as wide as possible when it touches the ground: but, as this breadth would be inconvenient in the air, by occasioning a greater resistance while he is moving along, no sooner does he lift the hoof than the two parts into which it is cloven fall together, and so lessen the surface exposed to the air, just as we may recollect the birds doing with their bodies and wings. The shape and. structure of the hoof are also well adapted to scrape away the snow, and enable the animal to get at the particular kind of moss (or lichen) on which he feeds. This plant, unlike others, is in its full growth during the winter season; and the Reindeer accordingly thrives, from its abundance, at the season of his greatest use to man, notwithstanding the unfavourable effects of extreme cold upon the animal system.

II.-MISCELLANEOUS

PASSAGES CONNECTED

WITH NATURAL HISTORY, GEOGRAPHY, &c.

EVENING SCENERY IN SOUTH AMERICA.

When the burning heat of the day is followed by the coolness of the night, which in these latitudes is always of the same length, even then the horses and cattle cannot enjoy repose. Enormous bats suck their blood like vampires during their sleep, or attach themselves to their backs, causing festering wounds, in which musquitoes, hippobosces, and a host of stinging insects, niche themselves. Thus the animals

lead a painful life during the season when, under the fierce glow of the sun, the soil is deprived of its moisture. At length, after the long drought, the welcome season of the rain arrives, and then, how suddenly is the scene changed! The deep blue of the hitherto perpetually cloudless sky becomes lighter; at night the dark space in the constellation of the Southern Cross is hardly distinguishable; the soft phosphorescent light of the Magellanic clouds fades away; even the stars in Aquila and Ophiuchus in the zenith shine with a trembling and less planetary light. A single cloud appears in the south, like a distant mountain rising perpendicularly from the horizon. Gradually the increasing vapours spread like mist over the sky, and now the distant thunder ushers in the life-restoring rain. Hardly has the surface of the earth received the refreshing moisture, before the previously barren steppe begins to exhale sweet odours, and to clothe itself with kyllingias, the many panicules of the paspalum, and a variety of grasses.

The herbaceous mimosas, with renewed sensibility to the influence of light, unfold their drooping slumbering leaves to greet the rising sun; and the early song of birds, and the opening blossoms of the water-plants, join to salute the morning. The horses and cattle now graze in full enjoyment of life. The tall springing grass hides the beautifully spotted jaguar, who, lurking in safe concealment, and measuring safely the distance of a single bound, springs, catlike, as the Asiatic tiger, on his passing prey.-HUMBOLDT'S ASPECTS OF NATURE.

CAPTURE OF THE GYMNOTUS (ELECTRICUS.)

The capture of the gymnoti (electric eels) affords a picturesque spectacle. Mules and horses are driven into a marsh which is closely surrounded by Indians, until the unwonted noise and disturbance induce the pugnacious fish to begin an attack. One sees them swimming about like serpents, and trying cunningly to swim under the bellies of the horses. Many of these are stunned by the force of the invisible blows; others, with manes standing on end, foaming, and with wild terror sparkling in their eyes, try to fly from the raging tempest. But the Indians, armed with long canes of bamboo, drive them back into the middle of the pool. Gradually the fury of the unequal strife begins to slacken. Like clouds which have discharged their electricity, the wearied fish begin to disperse; long repose and abundant food are required to replace the galvanic force which they have expended. Their shocks gradually become weaker and weaker. Terrified by the noise of the trampling horses, they timidly approach the bank, where they are wounded by harpoons, and cautiously drawn on shore by non-conducting pieces of dry wood. Such is the extraordinary battle between horses and fish. That which forms the invisible but living weapon of this electric eel; that which, awakened by the contact of moist dissimilar particles, circulates through all the organs of plants and animals; that which, flashing from the thundercloud, illumines the wide skyey canopy; that which draws iron to iron, and directs the silent recurring march of the guiding needle; all, like the divided hues of the ray of light, flow from one source; and all blend again together in one perpetually, everywhere diffused, force or power.-HUM

BOLDT.

UNIVERSALITY OF LIFE.

When the active curiosity of man is engaged in interrogating Nature, or when his imagination dwells on the wide fields of organic creation, among the multifarious impressions which his mind receives, perhaps none is so strong and profound as that of the universal profusion with which life is everywhere distributed. Even on the Polar ice the air resounds with the cries or songs of birds and with the hum of insects. Nor is it only the lower dews and vaporous strata of the atmosphere

which are thus filled with life, but also the higher and more ethereal regions. Whenever Mont Blanc or the summits of the Cordilleras, have been ascended, living creatures have been found there. On the Chimborazo, eight thousand feet higher than Etna, we found butterflies and other winged insects, borne by ascending currents of air to those almost unapproachable solitudes, which man, led by a restless curiosity or unappeasable thirst of knowledge, treads with adventurous but cautious steps: like him, strangers in those elevated regions, their presence shews us that the more flexible organization of animal creation can subsist far beyond the limits at which vegetation ceases.

The Condor, the giant of the vulture tribe, often soared over our heads, above all the summits of the Andes, at an altitude higher than would be the Peak of Teneriffe if piled on the snow-covered crests of the Pyrenees. The rapacity of this powerful bird attracts him to these regions, whence his far-seeing eye may discern the objects of his pursuit, the soft-wooled Vicunas, which, wandering in herds, frequent, like the Chamois, the mountain pastures adjacent to the regions of perpetual snow. But if the unassisted eye sees life distributed throughout the atmosphere, when armed with the microscope we discover far other marvels. Rotiferae, Brachionae, and a multitude of microscopic animalculae, are carried up by the winds from the surface of evaporating waters. These minute creatures, motionless, and apparently dead, are borne to and fro in the air until the falling dews bring them back to the surface of the earth, dissolve the film or envelope which incloses their transparent rotating bodies, and, probably by means of the oxygen which all waters contain, breathe new irritability into their dormant organs. According to Ehrenberg's brilliant discovery, the yellow sand or dust, which falls like rain on the Atlantic, near the Cape de Verde islands, and is occasionally carried even to Italy and Middle Europe, consists of a multitude of siliciousshelled microscopic animals. Perhaps many of them float for years in the upper strata of the atmosphere, until they are brought down by vertical currents, or in accompaniment with the superior current of the trade-winds, still susceptible of revivification, and multiplying their species by spontaneous division in conformity with the particular laws of their organization. But, besides creatures fully formed, the atmosphere contains innumerable germs of future life, such as the

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