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Buddhistic, and sometimes Brahmanical; but Buddhism was fast losing ground.

We next come to the important dynasty of the Gupta kings. Their sway lasted from 150-318 A.D., and was the most glorious ever wielded by native princes in India. Their capital was probably Saketa (Ayodhyâ, Oude), and their original domains east of the Ganges. They are said to have been Vaiçyas (of the third caste); which, being quite contrary to the code, implies a kind of social revolution, whereby the lower classes seized upon the privileges of the higher. Although Brahmanical in religion, and giving through their personal influence an impulse to Brahmanism, they accorded an enlightened toleration to Buddhists. The first king, Gupta, had probably been the satrap of a king Vikramaditya, who founded an empire at Crâvastî about 150 A.D.; and either he or his son Ghatotkaca made himself independent. The third king, Candragupta I. (crowned 168 A.D.), extended his dominions, and took Eastern Malava. Samudragupta (crowned 195 A.D.) made all Northern India as far as Bengal tributary; and was evidently as politic as he was great, his system being to confirm the princes of Northern India, a mountainous and easily defensible region, in their possessions, at the same time making them tributary to himself; and to let the princes of the Dekhan, a region still more inaccessible to conquest, simply feel his power, and to encourage them to resort to him for the settlement of their disputes. He was a great patron of the fine arts and letters; and to his reign, perhaps the most brilliant period of Sanskrit literature, are probably to be referred many of the poets and poems currently ascribed to that of Vikramaditya. His son, Candragupta II. (crowned 235 A.D.), added Kaçmíra to his empire; and Candragupta's son, Kumâragupta, or Skandagupta (reigned 240-270 A.v.), also Surâshtra ; after whom the empire apparently declined, and events (including a short usurpation of independence at Pâtaliputra) are obscure, until in 319 the Guptas are supplanted by the Ballabhi dynasty in Guzerat. Upon the next age we have not space to enter; nor would it be easy to give of it even as slight a sketch as the foregoing, deprived as we are at this point of the guidance of Professor Lassen.

ART. V.-THE PHASIS OF FORCE.

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The Correlation of Physical Forces. By W. R. Grove, Q.C., M.A.,

F.R.S., &c. Third edition. London: 1855. 8vo, pp. 229. On the Mutual Relations of the Vital and Physical Forces. By

William B. Carpenter, M.D., F.R.S., F.G.S., &c. “Philosophical

Transactions, 1850." The Phasis of Matter ; being an Outline of the Discoveries and

Applications of Modern Chemistry. By T. Lindley Kemp, M.D.

2 vols. London : 1855. Post 8vo, pp. 558. The Chemical and Physiological Balance of Organic Nature. By

MM. Dumas and Boussingault, Members of the Institute of France. Third edition, translated from the French. London : 1814. Fcap.

8vo, pp. 156. That "there is nothing new under the sun,” is an apophthegm more applicable to matter than to mind, and more truly represents the results of physical inquiry than those of an attentive survey of the moral history of man. For in the latter, progress is the rule ; whilst retrogression can scarcely be called an exception, so seldom is it real. But in the Cosmos, cyclical repetition every where seems to prevail. The alternation of day and night gives us our first and simplest experience of this revolution; the succession of the seasons our next; and although no one diurnal period is divided exactly like that which precedes or that which follows it, and although in no two succeeding years do spring, summer, autumn, and winter follow precisely the same course; yet when terms of sufficient length are compared, minor irregularities disappear, the general averages become wonderfully accordant, and limits are marked out beyond which we need not expect any aberration. As the earliest astronomers learned to predict eclipses by comparison of their recurring cycles, so those disturbances in the movements of the planets, and that displacement of even the sun himself, which the theory of universal gravitation predicts as its necessary results, and which modern observation shows really to occur, have the law impressed upon them, “thus far shalt thou go, and no further ;” being found by computation to pass through a cycle, whose duration, though capable of being expressed in figures, cannot be definitely conceived by the mind.

Not less obvious is this tendency to cyclical repetition in the changes which are constantly taking place in the substance of our globe, and in the living inhabitants of its surface. Of the aggregate of these changes, the oscillations of the magnetic

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needle may, in some degree, be taken as an expression; and the variations which are discernible in these, by careful and continuous observation, are found to be eminently cyclical. Besides diurnal, monthly, and annual variations of considerable regularity, which are traceable to changes in the place of the sun and moon, but which are occasionally interrupted by “magnetic storms” that put the compasses in different parts of the world into simultaneous agitation, there is a variation of very constant rate in the northward and southward pointing of the compass, between certain extreme easterly and extreme westerly limits, which extends over a cycle of centuries; and there can be no doubt that this is indicative of some correspondingly regular change in the interior of the globe; though as to its nature, only the vaguest speculations can at present be offered.

If now, with the geologist, we examine the structure of such parts of the solid crust as lie within reach of our scrutiny, the evidence of cyclical change seems at first sight to fail us; for according to the current hypothesis, whilst the original molten mass nearly uniform in its consistence and composition, gradually losing heat from its exterior, has been skinned over (as it were) with a solidified shell, the structure of that shell has been so modified by physical, chemical, and vital agencies, that its substance has been gradually differentiated into a series of layers, dissimilar both in mineral structure and in chemical composition; and this without any apparent tendency to return to its original homogeneousness. Yet when we examine the successive stages of this progress, we find in every part that the disturbing agencies have acted in cyclical periods, and that one cycle has been very much the repetition of another. The two great opposing agencies, fire and water, have been in antagonistic operation from the first. The one has been continually upheaving, the other yet more constantly degrading. The one has fused together minerals of the most dissimilar nature into formless masses; the other has not only worn these down and deposited them in successive layers, but has also separated their components in various ways; so that we find clays and sandstones, slates and limestones, shales and conglomerates, interstratified with more or less of regularity. And the more carefully the history of these deposits is studied, the more does it become apparent that they owe their existence to frequently-recurring series of changes, essentially the same in their nature, though modified in their results both by what has preceded and what has followed them.

Throughout the whole, one thing remains unchanged,—the absolute quantity of each of the elementary forms of matter; for whatever may be the new chemical combinations into which they enter, whatever the new physical arrangements to which they are subjected, their aggregate is the same now as it was at first. Every speculative philosopher is ready to admit the axiomatic truth of the proposition, Nihil fit ex nihilo. And the converse, Nihil fit ad nihilum, would be at once recognised as a no less necessary part of our belief, if it were not apparently corrected by familiar experience. But the researches of modern chemistry have most clearly established, that in this point, as in many others, familiar experience is quite in the wrong; that the annihilation of matter is as impossible to man as its creation; and that in every instance in which such a destruction seems to be effected, there is in fact nothing but a change of form. Thus the children of every primary school are now taught,—what was a new fact to the greatest philosophers no more than seventy years ago,—that in every act of ordinary combustion, the disappearance of the combustible is simply due to the formation of new compounds between its elements and the oxygen of the air, and to the diffusion of these compounds through the atmosphere; the decay of organised bodies being merely a slower kind of combustion, whose products are essentially the same in kind, and are disposed of in like manner. When we inquire into the nature and origin of either class of substances, we find that this dissemination of their materials through the atmosphere, merely restores to it what was originally taken from it by the agency of living beings; thus completing a cycle whose marvellous nature requires a somewhat fuller consideration.

The component elements of all vegetable and animal structures are essentially the same; namely, oxygen, hydrogen, carbon, and nitrogen, with a larger or smaller proportion of certain saline substances, which for our present purpose we may leave out of consideration. Of these elements, the first three alone exist in starch, gum, cellulose, chlorophyll, sugar, oils, and many other “proximate principles” which abound in plants; and as the greater part of their fabric is made up of such principles, their chief constituent, carbon, is the characteristic element of the vegetable kingdom. All four, however, are united together in the albumen, fibrine, gelatine, and other materials of which the animal tissues are essentially composed; and thus nitrogen comes to be the characteristic element of the animal kingdom. It exists, however, universally in the growing parts of plants, the presence of an albuminous substance being essential in them, as in animals, to the formation of new tissue; while the production of albuminous compounds, which are stored up in large amount in seeds and fruits, seems to be the chief end and aim of plant life.

Now whatever may be the amount of nutriment drawn by plants from the soil in which they grow, every vegetable phy, siologist is aware that this is ultimately derived from the atmosphere. Many trees will thrive without any soil whatever; and others give back, by the decay of their successive crops of leaves, more than they take from it. It is only the removal of the products of a rapid herbaceous vegetation, that really exhausts a soil, by withdrawing from it more than is given back by decay plus that which is absorbed from the atmosphere during the process. But it is not by directly uniting the oxygen and nitrogen of the atmosphere, with carbon and hydrogen supplied by vegetable mould, that the starch, chlorophyll, and albumen, are made, which furnish the materials of the vegetable fabric. The plant seems only to have the power of combining these elements into ternary and quaternary compounds, when they are being disengaged in the nascent condition from the state of binary combination which is characteristic of the inorganic world. Carbonic acid, which does not ordinarily form more than one two-thousandth part of the atmosphere,—and ammonia, whose universal diffusion through the air is unquestionable, though its proportion is almost inappreciably small, -constitute, with water, the essential pabulum of vegetable existence; but it is only under the influence of Light, that their elements can be separated from each other and recombined into their new forms. The growing plant, exposed to sunlight, has a decomposing power for carbonic acid, such as no other chemical agent possesses; setting free the oxygen, it retains the carbon ; and in the very same act, as it would

appear, generates both starchy and albuminous substances by the union of this carbon with the elements of water and ammonia. Hence the effect of vegetation on the atmosphere is, to be continually diminishing its carbonic acid and ammonia, and at the same time to be augmenting its proportion of oxygen. Even during the most vigorous life of the plant; however, it restores a part of its carbon to the atmosphere by a process analogous to the respiration of animals, in which, by union with atmospheric oxygen, this carbon reassumes the form of carbonic acid. And when the term of existence, either of the whole fabric or of any part of it (as the foliage), has been completed, the dead tissue, if freely exposed to the contact of air and moisture, undergoes a gradual decay, and is at last resolved by a series of metamorphoses, in which atmospheric oxygen is largely consumed, into the three binary compounds at whose expense it was at first generated, namely, carbonic acid, water, and ammonia. But if air be partially secluded, the process of decay is less complete; various new compounds are formed, which are rich in carbon and hydrogen, but poor in oxygen, and are therefore eminently combustible : yet these have a character of

permanence which indisposes them to spontaneous change; and thus

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