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homage required, is of the understanding as well as the affections. If we reverence the great Ruler of the universe, we shall show our confidence in him, by receiving everything that we believe to be from him, with the utmost deference. Cannot we comprehend his statements? Alas! for the feebleness of our intellect; but not for their truth. They are above, but not contrary to, reason. We bow to them, and will continually act upon them, rejecting with abhorrence those feelings that would render it necessary for man to be God. And then, we may remark, that this state of mind will bring its own reward. If, to know more, we must be more, as a recent philosophical writer has observed, we must experience, before we can know. To experience the power of religion, our blessed Saviour says, we "must be born again." If we do his commands we shall know whether they are of God or men.

Be it ours, then, Young Men, to press forward, with the most profound humility, to the great temple He has erected for His praise, intent on learning and worshipping, and not on dictating; and then He will reveal Himself unto us as He does not unto the world.

ON THE EVIDENCES OF UNITY AND DESIGN DISPLAYED IN THE ORGANISATION OF ANIMALS.

BY R. D. GRAINGER, ESQ., F.R.S.

[Under this title, a few unconnected papers have been contributed to the "STUDENT," in furtherance of the admirable objects advocated by the conductors of this Journal. At the request of these gentlemen the author has allowed his name to be attached to these brief notices, which will, for the future, be written with more attention as regards systematic arrangement, and, it is hoped, with less irregularity as to publication.]

ON THE NERVOUS SYSTEM.

If the organs of the external senses be excluded, the nervous system presents for our consideration instances of unity of plan, rather than of design in organisation; and for this sufficient reason-to the limited comprehension of man, design, or, as it has also been termed, purpose in organisation, can only be demonstrated when the mechanism is so obvious as to fall within the grasp of our observation. Now, as regards the nerves, and their central organs-the brain and the spinal marrow-their operations are so subtle, and their ultimate texture is so refined, that it is doubtful if the precise mode in which they operate will ever become apparent to human apprehension. At all events, notwithstanding the late and rapid advances of science, the existing state of knowledge leaves this interesting point of physiology wrapt up in

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all its original obscurity. Nor, we may further remark, can this be matter of surprise, when it is recollected that the nervous system is the very instrument of animal life-the agent through which operates the sentient being-the organ that constitutes the last link of connexion between the material body and the immaterial spirit. If, then, in an organisation thus refined, we in some degree fail to detect an adaptation of means to ends, it is necessary to infer that our want of success is attributable rather to defective means of research, than to an actual deviation from what is so distinctly proclaimed to be in all other instances the fixed condition of animal structure; an inference which is supported not only by analogical reasoning, but likewise by an examination of several parts of the nervous system itself.

We may, in the first place, illustrate the position that there is uniformity in the plan, according to which the organs of innervation are constructed. This is the more necessary, inasmuch as some high authorities-amongst whom Cuvier holds a prominent place-contend that, in the several divisions of the animal kingdom, where a nervous system can be demonstrated, the plan is different; or, in other words, that there is no unity of composition in the vertebrata, articulata, mollusca, and radiata. To make ourselves understood, we must explain the meaning attached in this paper to the expression "unity of plan;" by it is signified, that, setting aside as things indifferent, form, colour, and position, there are in the nervous system of all animals, vertebrate or invertebrate, certain principles or types of formation which are essential, are, therefore, in no case absent, and which, being thus present, constitute identity of organisation.

The constant and necessary parts of every nervous system* are, first, certain masses of a greyish substance, called, in a general way, ganglia; and, second, certain threads of a whitish colour, termed nerves, or nervous fibres. Both these materials require, for the revelation of their true structure, the aid of the microscope. If the former, or the grey substance, be thus scrutinised, it is seen to be composed of certain particles, extremely minute, called ganglionic globules, or corpuscles, having attached to, or placed between them, delicate threads and fibres. As regards the nervous fibres, they for the most part consist of membranous tubes or canals in which the nervous pulp is lodged, and so small that their diameter varies from Tooo to Toooo of an inch. Of these two essential substances, it can be shown that the grey, or corpuscular portion, is the seat of all nervous power, and is consequently met with in what are hence called nervous centres, of which the best known to non-professional persons are the brain and the spinal marrow; whilst with respect to the tubular portion, it serves to transmit the impressions or impulses originating in the active centres, each of the tubes of which it consists acting as an isolated conductor.

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Such, then, being the organic structures, the question rises, are they present in all animals in which a nervous system has hitherto been detected? Minute anatomy has satisfactorily replied to this query in the

There is a third substance, composing what are named by anatomists the gelatinous fibres; but it would lead to unnecessary detail to describe them.

affirmative, by showing that the grey substance has an existence coextensive with this system; that it consists, in the lowest as in the highest classes, of the same elementary globules, and that the nerves invariably consist of the well-known tubes above described. So far, therefore, as the main point-that is, the ultimate structure-is concerned, the position as to uniformity must be regarded as established; and this being once proved, all else is in reality a matter, not of essentials, but of details. It will not, however, be difficult to show that even as respects the arrangement, there are certain fundamental principles from which, whatever may be the apparent deviations, there is no real departure. In reference to this part of the question, concerning as it does the various modifications of disposition met with in animals, we can only offer a few general remarks, and those applicable to the three higher divisions of the vertebrata, articulata, and mollusca.

In these classes there are to be recognised, however much masked by irregularity in disposition or concealed by minuteness in size, a brain, a spinal cord (or, more correctly, a spinal system), and nerves. In making this assertion, we are not unmindful that many high authorities may be arrayed in opposition to it; that some zoologists, for example, deny a brain to insects and to the articulata generally; and that others would withhold the same organ from the mollusca, even from the highest among them, the cephalopoda, including the cuttlefish. But these and similar notions were, for the most part, broached before the true relations of the spinal marrow and brain were determined; and therefore require to be reviewed with the aid of the great light that has in late times been thrown upon this, the most important, but, at the same time, the most abstruse, of all the questions bearing on neurology. The great luminary of modern physiology, the late Sir Charles Bell, had more just conceptions upon the relations of the nervous system in the vertebrate and invertebrate animals. He says, speaking of the spinal nerves in man, "We see thirty-one nerves, similar in origin and constitution, ranging with perfect order, and going forth to the head, body, and limbs in regular succession; and in their essential attributes, common to every class of animals, from the creeping thing up to man." The splendid researches of that great man have fixed the fundamental laws of innervation on a basis that nothing can disturb; and one of the most essential of these laws is uniformity of plan.

It would be out of place to enter here upon the anatomical details substantiating the grand axiom announced by Bell; one or two illustrations only can be adduced. In the first place, with respect to the brain, we find that it consists, in man and the vertebrata, of certain masses placed symmetrically on the two sides of the vertical median plane of the body; the brain increases in the number and size of its parts, in proportion as the range of sensation is developed; and, lastly, it sends off certain nerves of the senses, among which are included those of the eyes, or optic. So, in like manner, the brain of the avertebrate animals is composed of certain masses (very commonly confounded together by careless anatomists) placed symmetrically on the sides of the median plane; so, again, the brain increases in its parts

and magnitude, in exact relation to the extension of the sentient phenomena, of which the metamorphosis of the larva into the imago, or perfect insect, affords a complete demonstration; and, finally, it furnishes the nerves of special sense, of which the optic are most conspicuous. The evidence, as regards the spinal system, is even more full and striking. In the vertebrata, it enlarges in the exact ratio of the magnitude of the attached nerves; it furnishes a series of nerves arising in a very complex and peculiar manner; and it is the seat of certain important powers essential to the maintenance of animal existence. If we turn to the articulate and molluscous animals, there is no difficulty in demonstrating the same essential facts: there is a spinal system proportioned definitely, and in all cases, to the size of the nerves; there are nerves, which in the instance of the articulata particularly, arise precisely in the same complex and peculiar manner as they do in man and the vertebrata; and, to crown all, the powers of this spinal apparatus are of exactly the same nature as in the highest classes.

With evidence such as this, the arguments derived from diversities of form and position go for nothing. It matters not, for example, that in the earth-worm the brain is composed of two minute points of neurine, so small, indeed, and so much imbedded in the soft mass of the head, as to be scarcely discoverable; it is not the less a brain for these reasons; it serves, indeed, as the best starting-point to enable us to comprehend the human cerebrum, to which comparative anatomy, that unerring guide, as surely conducts us through the several classes of the insecta, myriapoda, arachnida, and crustacea, as if we had only commenced the ascent from the lowest cartilaginous fishes. Nor does the objection, that in the invertebrata the spinal system is placed upon the abdominal, whilst in the vertebrata it is lodged upon the dorsal aspect of the alimentary canal, carry any weight with those who, accustomed in the study of organisation to seize the typical and essential structures, reject in the interpretation of animal formations all that can be shown to be secondary, and therefore indifferent.

The evidence adduced in the preceding remarks, to establish the fact that there is, in the construction of the nervous system, unity of plan, has been derived from three distinct sources:-the ultimate texture, the disposition of the constituent parts, and the uses they fulfil. And we will only further observe, that proofs of this kind, which could be indefinitely extended, are more likely to receive the assent of the thoughtful and reflective among the general public, than the fanciful attempts which have been made, especially by some French naturalists, to force a resemblance between the position of the various organs in the vertebrate and invertebrate sub-kingdoms, which has no real existence in nature.

In our next paper, we purpose to give a sketch of the mechanism provided for the protection of the various parts of the nervous system.

WORDSWORTH.

THE popularity-or, as authors are better pleased to term it, the fame -of a poet has many causes. Some attain a temporary pre-eminence by the contrasted weakness of their rivals, and enjoy the merely comparative grandeur which attaches itself to one-eyed monarchs of the blind; some acquire reputation by the singularity of their style, which, however monstrous in character, is yet devoured with delight by the million, since it ministers to their never-cloying appetite for changebecause, in short, the frantic efforts of a depraved imagination are confounded with the dignified achievements of true genius. These remarks, of course, apply only to the celebrity of an author in his own day; posthumous celebrity, however slowly confirmed, being seldom unjustly so. The most decided arbiters of public opinion are the censors of periodical literature; but with what degree of passive and reverential credulity we should acquiesce in their decision, is certainly an important consideration. Putting out of the question the frailty of human judgment, as an error to which all are alike liable, we perceive that there are many other causes which interfere to prevent unbiassed criticism. We learn that prejudice, by a thousand obstructions, turns the current of opinion into false channels; that political differences, the gratification of individual pique, the subserviency of the weak to the strong, the difference of interests between party and party, alike militate against a just expression of judgment, and mix their alloy with the pure sincerity of criticism. A feeling of envy, too, which is a portion of the inherent weakness of humanity, operates powerfully on many minds while contemplating the efforts of original genius; the consciousness of mental superiority in another seems unwillingly impressed upon them; it is a painful discovery, and if it be possible to detect an imperfection, they dwell upon and expose it with a jealous delight.

The foregoing causes for many years prevented Wordsworth from taking his true place among the chief poets of our country. This fault has now been repaired by the public, and although slowly, yet he has surely gained his proper station in the very first rank of those great spirits whose extraordinary talents have rendered the age illus

trious.

Even now, perhaps, of all our great poets, Wordsworth is least read; and if he is little read, he is less understood. That there are some grounds for this neglect cannot be denied. Wordsworth, in his search after simplicity, has sometimes allowed it to seduce him from the goal at which he aimed. So convinced is he that the true sublime is founded on simplicity, that he has not unfrequently followed up his darling principle till it has led him into absurdity; and this is a fault more injurious to an author's reputation than extravagance, or even than the monotony of tameness. It is undeniable, that on instituting an examination of his writings, we find much puerility and more dulness; we are frequently disgusted by affectation of babyish simplicity, and repelled by the cold, prosing tone of the philosopher,

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