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ART. IV.-1. The Natural History of Creation. By T. LINDLEY KEMP. London: Longmans, 1852.

2. Indications of Instinct. By T. LINDLEY KEMP; being Nos. 24 and 54 of the "Traveller's Library." London: Longmans, 1854.

THES

HESE two little books, by the same author, are popular expositions of not a few topics of the highest interest and importance. Dr. Kemp has successfully studied the art of popular writing on subjects of science. This is no small praise, for the greatest number of our modern popular scientific treatises are composed in a manner not at all level to the apprehension of the parties for whose use such books are intended. Many of these are meagre enough as respects the amount of knowledge which they convey, yet full of details as far as they go. But details, however important, should hold but a secondary place in a popular treatise, while the main attention should be devoted to supplying the reader with ideas, so as to enable him to enter into the spirit of the subject under consideration, and to make way for his easier apprehension of the purpose and bearing of the details. It is true that the English mind, owing to its decidedly practical turn, seeks details, and hardly feels that it is acquiring knowledge while nothing but general views and principles are communicated. And this, doubtless, is the reason why so many treatises which have popular" printed on the title-page, exhibit so little of a popular character in their interior. The authors indulge the national humour, and fill their books with particulars, but with what result? certainly with no success in spreading through new circles of society the knowledge of the subjects which they have undertaken to teach. Their readers can see that, according to the standard of ample detail, the books are excellent, but they come to the conclusion that such studies are either not suited to the meagreness of their present ideas, or to the stinted leisure which they can command from their habitual avocations. If, then, any great progress is hereafter to be made in imparting to the general public a knowledge of scientific subjects, a change of plan must be made in our popular

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treatises the public taste for the appearance of particulars must not be indulged, but counteracted, while means must be found of reconciling people to the cultivation of general notions, ideas, and principles, in the various branches of scientific research, as preliminary to the attainment of a better facility for the apprehension and remembrance of the particulars of the sciences.

"The Natural History of Creation," the first of the works at the head of this article, is a duodecimo of 123 pages. It is designed to exhibit the general character of the three great departments of nature, the mineral, the vegetable, and the animal kingdoms, the modes in which these are connected together, and the plan on which the existence of the two organic kingdoms is developed and maintained. The treatise is wholly elementary, and throughout most intelligible. The titles of the two first chapters are," The living and the dead occupants of the globe," and "The way the blood is circulated; those of the two last are, "The way people die," and "The ways the doctors have of preventing death."

The second of the two works, namely, "Indications of Instinct," is a duodecimo of 144 pages. Of this we wish to speak a little more fully.

Dr. Kemp gives a large extension to the idea of instinct. He regards instinct as belonging not merely to the higher orders of animals, but as displayed in the acts of the very lowest tribes of the animal kingdom, and even in the vegetable creation. Nevertheless, if we understand our author aright, he limits the operations of instinct to what physiologists term relative acts, that is, to acts by which the organic system establishes direct relations with things without, exclusive of the acts immediately subservient to its own proper development and maintenance. Such relative acts are commonly regarded as peculiar to animals, and were indeed formerly known distinctively as the animal functions, the attributes by which animals are in particular distinguished from vegetables. It is undeniable that the functions, namely, the operations of sense and voluntary motion, by which the higher animals, and man in particular, acquire a knowledge of nature, and a power over it, are essentially the attributes of the animal kingdom; nevertheless, these functions dwindle to a minimum in the lowest tribes of animals, and are replaced in plants by acts which, though manifestly different in their physiolo

gical character, are yet often strictly analogous in their effects. Thus, when a man gathers dates from a datepalm, he performs an act of relation; he exerts a power over nature; but when these dates, received into his stomach, undergo digestion, and pass into chyme, the act is termed physiologically an organic or vegetative act, and falls under that class of functions which is common to all organic nature, to plants as well as to animals. But to take an example from the work before us. The bean contains a large proportion of alkali, and a small proportion of siliceous earth, while barley contains a large proportion of a siliceous earth, and a small proportion of alkali, and the roots of these two plants spread out in the same field till each has obtained the requisite quantity of these two elements. It is true the acts in these contrasted instances of the animal and vegetable kingdom differ essentially in the organization by which they are severally effected, but in their general result there is a strict analogy, so that it does not seem unreasonable to admit this extension of the radicles of such plants as the bean and barley to the rank of relative functions.

When, then, our author admits certain operations of plants to the rank of instincts, it is to be understood that such operations uniformly bear a strict analogy to what are termed the relative acts of animals. He does not, in short, destroy the use of the term instinct, as some have done, not without plausible reasons, when they have considered all the operations of organic nature as bearing one character of instinctive acts-speaking even of the chemical phenomena exhibited in the development and repair of living structures as the results of instinctive affinities. In such an excessive extension of the term instinct, it becomes confounded with the operations of vitality. We admit, however, that such a view has a foundation in the strict analogy which exists between the results produced by the operations of the molecular constituents of the solids and fluids of living nature, so strongly suggestive of the direct presence of an intelligent agency, and those wonderful performances determined in animals by that inward impulse to which ordinarily the name of instinct is applied.

Among the instances of instinct in plants, Dr. Kemp enumerates the opening and shutting of flowers; the movements of the stamens in certain flowers, by which the

pollen is communicated to the stigma, the change in the direction of the leaves in many plants, as in what is termed the sleep of plants, one of the ordinary effects of which is, to conceal and protect the flowers; also the singular effects witnessed in the Dionæa muscipula, or Venus' flytrap, in the several species of Drosera, or sun-dew; the species of Oscillatoria among the jointed algæ, the phenomena of climbing plants, and the acts already referred to by which many plants extend their radicles along the adjacent soil till the proper kind of food is attained. Viewed as relative acts, that is, as acts falling under the same head as the acts of knowledge and power exemplified in the higher animals, such phenomena have plainly a rudimentary character; still, they are more allied to relative phenomena than to those direct acts of assimilation, which, under the guidance of a vital chemistry, are performed in the ultimate cells of the vegetable texture. Hence, if all the functions of organic nature, both vegetable and animal, be exhausted under the three heads, vegetative, reproductive, and relative, the above enumerated phenomena of the vegetable kingdom must necessarily fall under the head of relative phenomena, and, therefore, claim a place under instinct as justly as any analogous phenomena in the animal kingdom. They are acts of a rudimentary relative character, essential to some required use in the economy of the plants which exhibit them, and determined by the presence or by the more or less frequent recurrence of an adequate stimulant agency.

Among the instances of instinct referred to by our author in the lowest tribes of animals, are the following: Some of the infusories, animals so minute that hundreds of thousands of them may exist in a single drop of water, rotate the bristles or tenacles around their mouths, by which a current of water, containing their food, is determined into their mouths; polypes fix themselves to rocks less exposed to violent currents, and apparently, if there be a deficiency of light in their first place of abode, they move towards a lighter place of abode, and when they seize their food, they put out no more of their long arms than is necessary to overpower their present prey; the coral polypes, after having reared an island above the surface of the sea, with a lake in its centre, leave a communication between this lake and the sea, by which a due supply of food and building materials may enter; the sea

anemones present at times the appearance of expanded flowers, fixed to rocks at the bottom of the sea, and when all is quiet these apparent flowers come up to the surface, but on the slightest indication of danger, instantly descend, and nothing is there to be seen but a fleshy mass, sticking so fast to the rocky bottom, that it cannot be removed without tearing its structure to pieces; the young salpes, whose structure is frail, like that of a thin jelly, unite themselves together for mutual protection, by means of lateral suckers, and when after a time a greater stability of structure is attained, the instinct of association ceases, and the several individuals separate; these salpes being the lowest animals in point of organization, which possess the instinct of association for mutual support; the pholads, or stone-borers, little animals living in a fragile bivalve shell, bore a hole after a definite plan, in the hard rock, which may serve them for a habitation; among the bivalve shells, such as the oyster, the clam, and those of the genus venus to which the wampum belongs, singular instincts are observed, as for example, that by which the oyster, by suddenly squirting out water, throws its enemy, the crab, on its back, and those by which some of the others use one of their shells as a sail, when at the surface, in a gentle breeze; the remarkably complex movements, by which the common garden snail prepares in autumn for hibernation, the chief object of which is, to provide a supply of air for its respiration during the time occupied, on the return of spring, in working itself out of its winter prison; the condylope, termed the pest of the perch, the hermit-crab, the genus crab in general, and the spider tribe, with their generally known singular instinctive habits, conclude this interesting chapter.

The next chapter is devoted to the instinct of insects, in which much attractive matter is added, to what is so generally known on this subject, the singular habits of ants and bees affording the principal themes of the chapter.

In the next chapter, on the instinct of fishes and reptiles, many curious facts are related. Among others we find a notice of the fish termed the fly-shooter, which the Chinese often keep for amusement in their houses, the singularity in its habits being the accuracy with which it darts a drop of water at such insects as come within reach, so as to kill or stun them for prey. Again, a notice of the

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