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From the come fishes seems to beled by the relihing air whenco

ment which thers haven a certain itance of when the

with some probability, that the chief use is to avoid the inconvenience arising from the rapid flight, by furnishing air when the action of the lungs is incommoded by the resistance of the medium. Respiration seems to be, in a certain degree, necessary also to some fishes. Others have the power of extracting air from the element which they inhabit; either by decomposing the water, or by separating the gas which it contains.' The organs of respiration in insects are generally fligmata, or small holes, ranged along the sides in regular and beautifully dotted lines. If these be covered with any unctuous substance, the animal soon perishes. Some insects are furnished with trachea. which protrude from different parts of the body, and sometimes have the appearance of tails, There is a species of aquatic worms, of a greenish brown colour, the bodies of which confift of eleven rings, the last being open, and serving as a conductor of air. From this proceed a number of hairs, which are real feathers in miniature, and exclude water or mud, that might obstruct respiration. Though air be, upon the whole, necessary to the support of animals, yet they can continue for a great length of time in a state of inaction, and without appearing to breathe, The facts with regard to the toad are very extra ordinary. Three toads were lately buried in a box of earth and, three months after, two of them were found still alive:

" At the approach of winter, the toad retires to the hollow root of a tree, to the cleft of a rock, and sometimes to the bottom of à ditch or pond, where it remains for months in a state of seeming in, senfibility. In this last situation it can have very little communica. tion with the air. But still the principle of life is continued, and the animal revives in the spring. What is more wonderful, toads have been found, in an hundred places of the globe, inclosed in the heart of solid rocks, and in the bodies of trees, where they have been fup. posed to exist for centuries, without any apparent access either to nourishment or to air; and yet they were alive and vigorous. In the Memoirs of the Academy of Sciences for the year 1719 we have an account of a toad found alive and healthy in the heart of an old elm. Another, in the year 1731, was discovered near Nantz, ia the heart of an old oak, without any visible entrance to its habita. tion. From the fize of the tree it was concluded that the animal muft have been confined in that situation at least eighty or an hundred years. In many examples of toads found in folid rocks exact impreffions of the animals bodies, corresponding to their respective fizes, were uniformly left in the stones or trees from which they were disodged; and to this day it is said that there is a marble chimney-piece at Chatsworth with a print of a toad in it, and a traditionary account of the place and manner in which it was discovered.'

| Chap,

Chap. IV. relates to motion. Motion, though the most familiar to our senses, is obscure and difficult, when considered in the abstract. Mr. Smellie very properly waves the metaphysical discussion of the subject. Motion may be divided into two kinds: that in which it originates in the body moved, and that in which it is derived from external action. The former includes the motions of animals, the latter those of inanimate matter. The energy which we exert has its source in the brain and its ramifications, composing the nervous system ; and we are stimulated into action by the sensations made by the impressions of the objects around. But there are other motions, which are termed vital or involuntary, such as the action of the heart, the periftaltic motion of the bowels, &c. ; in all which we are not confcious of the operation of our will. The motions of animals vary with their weight, their structure, their dispositions, and their mode of life. Timid animals betray a restlessness, and a continual flutter of action. Mr. Smellie selects several curious instances of animals which we would suppose from their structure remain constantly at rest, but which really perform a flow and painful motion. The níuscle transports itself by means of its tongue. It forms numberless viscous, threads, with which it can at pleasure attach itself to the rocks, and resist the agitation of its element. The razor-fish descends in the fand, by the projection and incurvation of its leg. The oyster retreats by suddenly and forcibly ejecting water. The motion of a species of Medusa, or fea-nettle, is as slow as the hour-hand of a clock: 1. The fea-urchin, or sea-hedgehog, is round, oval, or shaped like a bias bowl. The surface of the ihell is divided into beautiful triangular apartments, and covered with numberless prickles. These triangles are separated by regular belts, and perforated by a great number of holes. Each hole gives lodgment to a ficky horn, similar to those of the snail, and Tusceptible of the same movements. Like the snail, the sea urchin uses its horns when in motion ; but their principal use is to fix the animal to rocks, stones, or the bottom of the ocean. By means of the horns and prickles, which proceed from almost every point of the shell, the sea urchin is enabled to walk either on its back or on its belly. The limbs it most generally employs are those which surround the mouth. But, when it chooses, it can move forward by turning on itself, like the wheel of a coach'

[ To be continued. ]

ART,

Art. II. On the Principle of Vitality in Man, as described in the | Holy Scriptures, and the Difference between true and apparent 'Death; a Sermon preached in the Parish Church of St. Andrew,

Holborn, on Sunday, March 22, 1789, for the Benefit of the Humane Society. By Samuel, Lord Bishop of St. David's. 4to.

is. Rivingtons. London, 1789. IT is impossible to contemplate without pleasure this great

champion of the church against the inroads of Socinianism engaged in the benevolent office of preaching on the above oc-' casion. But neither the obligations we owe to his industry and learning, nor the high station he so deservedly fills, should prevent our discharging those duties the public has a right to expect of us. If therefore it should appear to us that this able and eloquent divine reasons better in polemics than on subjects of phy, fiology, we shall not scruple to hazard our credit in so bold a conteft.

After admitting that, on subjects of philosophy not connected with religion, it is possible that an inspired writer may have entertained erroneous opinions, or have accommodated himself to popular language, his lordship endeavours to shew that the compound nature of man, and the immateriality of the soul, are among those subjects of positive revelation which a Christian cannot but believe. This is a point we shall not take upon us to dispute ; though we cannot help doubting whether any of the terms by which the soul is described in holy writ necessarily imply its immateriality, how much foever they may teach us that its existence is unconnected with the body. But the inquiry we would wish to make is, whether from scripture or from reason we learn any just conceptions of the principle of vitality; or, if we do, whether they will enable us to distinguish between true and apparent death.

The following is his lordship’s account of the compound nature of man : :But now let the divine be careful what conclusion he draw from this plain doctrine, and what notions he engraft upon it. Although we must believe, if we believe our Bible, that the union of soul and body is the first principle of animation in the human subject, it is by no means a necessary consequence that the life of man is in no . degree, and in no part, mechanical. Since man is declared to be a compound, the natural presumption seems to be, that the life of this compounded being is itself a compound. And this experience and observation prove to be indeed the case. Man's life is com pounded of the life of the intellect and the animal life. The life of the intellect is fimply intelligence, or the energy of the intelligent principle. The animal life is itself a compound, consisting of the

vegetable

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vegetable life combined with the principle of perception. Human life therefore is an aggregate of at least three ingredients ; intelligence, perception, and vegetation. The lowest and the last of these, the vegetable life, is wholly in the body, and is mere me. chanism; not a mechanism which any human ingenuity may imitate, or even to any good degree explore; but the exquisite mechanism of a Divine Artificer. Still it is mechanism ; consisting in a symmetry and sympathy of parts, and a correspondence of motions conducive, by mechanical laws established by the Creator's wisdom, to the growth, nourishment, and conservation of the whole. The wheels of this wonderful machine are set a-going, as the scriptures teach

us, by the presence of the immaterial soul; which is therefore not I only the seat of intelligence, but the source and centre of the man's

entire animation. But it is in this circumstance only, namely, that the immaterial mover is itself attached to the machine, that the vegetable life of the body, considered as a distinct thing, as in itself it is, from the two principles of intelligence and perception, differs in kind (for in respect of excellence and nicety of workmanship all comparison were impious; but in kind the vegetable life of the human body differs in this circumstance only) from mere clockwork.

Nothing can be more painful to us than not clearly to comprehend the arguments of a learned and ingenious writer. When we read that the life of the intellet is simply intelligence, and

that the animal life is a compound of the vegetable life com• bined with the principle of perception,' we are led to suppose that these last two are sufficient for the support of life divested of intelligence; and by the term mechanism, which is afterwards made use of, we are inclined to believe that this is his lordship's meaning. But it is afterwards added, "The (wheels of this wonderful machine are set a-going, as the scrip(tures teach us, by the presence of the immaterial soul.' 'If by this be meant that the body, being once set in motion by the soul, continues that motion without the aid of the latter, we can admit the propriety of the terin used. But if the presence of the soul be always necessary for the continuance of that motion, then either the body is not a machine, or the soul is a part of it. If it were necessary to illustrate this, we need only use his lordship's language, and observe that a clock, when set as going by a man, continues, without his aid, its action afterwards for a time, according to the laws on which it is constructed, unless any of its parts are deranged. We are ready to admit the inference, that this mechanism is described as such as no human ingenuity can imitate, but we mean to urge that it does not at all illustrate it- Still it is mechanism ; consisting

in a symmetry and sympathy of parts, and a correspondence of émotions conducive, by mechanical laws established by the . • Creator's wisdom, to the growth, nourishment, and conser

Nation,

{ vation, of the whole.' If this means that the arrangement of the different parts are best calculated for the above purposes, no man in his senses will doubt it. If it means, as we fuspect, that without the assistance of the soul, all these purposes are brought about in other animals, and in vegetables; then either the soul is not necessary to set in motion the wheels of this machine, or animals and plants have a soul as well as man.

Setting aside then the word machine, which, from its ety. mology and common acceptation, is ill applied to what no art can imitate, and what is no way the subject of mechanical prins ciples, let us substitute the word organ, which, being a primitive word, is less liable to misconception. Let us then ask, whether any of the actions of this organ for the purpose of preserving and supporting itself, are so different from the organisation of other animals as to require a different mover; or if, as we are ready to admit because fcripture language implies it, the intelligent or immortal principle is different in man from those or. ganised materials ; whether it necessarily follows that this principle should be immaterial, when, by the above conceflion, we see how far common matter is susceptible of organisation. And, lastly, we leave it to his lordship's candour to determine whether the expressions he has selected from scripture, as descriptive of the soul, necessarily imply immateriality, how plainly soever they may describe an existence distinct from the body.

Having made thus free with the production of this learned prelate, it is but just, though hardly necessary, to observe that the rest of the sermon is admirably suited to the occasion, and replete with sound reasoning and judicious observations.

ART. III.

The First Principles of Chemistry. - By William Nic
cholson. 8vo. 8s. London, 1789.

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PERSPICUITY is the sole merit of an elementary trea-'

tise ; and the great object is to preserve a clear, connected arrangement. The facts ought to arise naturally out of each' other, and the mind ought to pass smoothly along a chain of continued succession. The phenomena must be gradually developed ; fimple and independent subjects must be first surveyed; and the effects of their various combinations will afterwards be perceived with facility. No branch of physics is perhaps more difficult to reduce to system than the science of chemistry; for the facts exist seldom independent, but are involved with collateral circumstances. The present is the critical era of the science. Its form has long been exposed to Auctuation and change; and laboured hypotheses have often perished in the

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perceive to reduceon independerent is the CFO Aluctuat

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