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NEWTON'S THEOLOGY.

We see in the theology of Newton the very spirit and principle which gave all its stability and all its sureness to the philosophy of Newton. We see the same tenacious adherence to every one doctrine, that had such valid proof to uphold it as could be gathered from the field of human experience; and we see the same firm resistance of every one argument that had nothing to recommend it but such plausibilities as could easily be devised by the genius of man, when he expatiated abroad on those fields of creation which the eye never witnessed, and from which no messenger ever came to us with any credible information. Now, it was on the former of these two principles that Newton clung so determinedly to his Bible as the record of an actual annunciation from God to the inhabitants of this world. When he moved his attention to this book, he came to it with a mind tutored to the philosophy of facts; and when he looked at its credentials, he saw the stamp and the impress of this philosophy on every one of them. He saw the fact of Christ being a messenger from heaven, in the audible language in which it was conveyed from heaven's canopy to human ears. He saw the fact of his being an approved ambassador from God, in those miracles which carried their own resistless evidence along with them to human eyes. He saw the truth of this whole history brought home to his own conviction by a sound and substantial vehicle of human testimony. He saw the reality of that supernatural light which inspired the prophecies he himself illustrated, by such an agreement with the events of a various and distant futurity as could be taken cognizance of by human observation. He saw the wisdom of God pervading the whole substance of the written message, in such manifold adaptations to the circumstances of man and to the whole secrecy of his thoughts and his affections, and his spiritual wants, and his moral sensibilities, as even in the mind of an ordinary and unlettered peasant can be attested by human consciousness. These formed the solid materials of the basis on which our experimental philosopher stood; and there was nothing in the whole compass of his own astronomy to dazzle him away from it; and he was too well aware of the limit between what he knew and what he did not know to be seduced from the ground he had taken by any of those

brilliancies which have since led so many of his humbler successors into the tract of infidelity. He had measured the distances of these planets. He had calculated their periods. He had estimated their figures, and their bulk, and their densities, and he had subordinated the whole intricacy of their movements to the simple and sublime agency of one commanding principle. But he had too much of the ballast of a substantial understanding around him to be thrown about by all this success among the plausibilities of wanton and unauthorized speculation. He knew the boundary which hemmed him. He knew that he had not thrown one particle of light on the moral or religious history of these planetary regions. He had not ascertained what visits of communication they received from the God who upholds them. But he knew that the fact of a real visit made to this planet had such evidence to rest upon that it was not to be disposted by any aerial imagination. And when I look at the steady and unmoved Christianity of this wonderful man, so far from seeing any symptom of dotage and imbecility, or any forgetfulness of those principles on which the fabric of his philosophy is reared, I see, that in sitting down to the work of a Bible commentator he hath given us their most beautiful and most consistent exemplification.-CHALMERS.

THE TELESCOPES OF SIR W. HERSCHEL AND LORD ROSSE.1

In respect of his own telescopes, Herschel computed that the seven feet reflector had an ability to penetrate into space, which, compared with that of the naked eye, was 201; the ten feet, a comparative power of 28; the twenty feet, of 75; the twenty-five feet, of 96; and the forty feet, with its four feet mirror, the immense power of 192. It is not easy to compare Lord Rosse's telescope with those instruments, inasmuch as other elements of great importance would require to be ascertained by direct experiment, but if, as seems fully established, his Lordship's three feet speculum is superior, in space-penetrating power, to the largest disc in possession of his great predecessor, we shall be obliged to endow the six feet mirror with an efficacy to pass without difficulty at least 500 times farther onwards than is possible for un

This nobleman has expended munificent sums in the construction, at Parsonstown in Ireland, of the largest reflecting telescope yet erected.

assisted vision: in other words, it will descry a single star six thousand times more remote than an average orb of the first magnitude; or, though it were separated from our abodes by an interval so tremendous that were a new star at a similar distance created now, its light, even though its velocity be next to inconceivable, would travel through the intervening space probably for more than sixty thousand years ere, by reaching this earth, it could tell of a new existence having been summoned from the void! The massive sphere through which the eye can now travel, having a diameter 500 times larger than that which belongs to unassisted vision, these instruments may be said to have enlarged our accessible universe by 125,000,000 of times-a sphere which, though it may be but a mere point or islet amid infinitude, is assuredly comprehensive enough to contain, if not all that man can desire to know, at least intimation the most precious of the nature of the majestic scheme to which it is his present destiny to belong.-NICHOL.

THE EARTH.1

The consideration of the increase of heat with the increase of depth towards the interior of our planet, and of the reaction of the interior on the external crust, leads us to the long series of volcanic phenomena. The elastic forces are manifested in earthquakes, eruptions of gas, hot wells, mud volcanoes, and lava currents from craters of eruptions, and even in the production of alterations in the sea level. Large plains and variously indented continents are raised or sunk, lands are separated from seas, and the ocean itself, which is permeated by hot and cold currents, coagulates at both poles, converting water into dense masses of rock, which are either stratified and fixed, or broken up into floating bergs. The boundaries of sea and land, of fluids and solids, are thus variously and frequently changed. Plains have undergone oscillatory movements, being alternately elevated and de

1 This paper forms a portion of Humboldt's general mapping cut of the telluric phenomena, whose illustration forms the chief subject of his work. In his theoretic delineation of nature (see p. 7) he has indicated the method of inquiry, supposing the student to commence with his terrestrial habitation, and to proceed to the regions beyond his native sphere; as an instructor he proceeds differently, and in his view of all that is known of the universe, he descends from the widest circle of space to the special phenomena of the Earth. In our arrangement of papers on the subjects with which M. Humboldt's work deals, we have in the main adopted this method.

pressed. After the elevation of continents mountain-chains were raised upon long fissures, mostly parallel, and, in that case, probably contemporaneous; and salt lakes and inland seas, long inhabited by the same creatures, were forcibly separated; the fossil remains of shells and zoophytes still giving evidence of their original connexion. Thus in following phenomena in their mutual dependence, we are led from the consideration of the forces acting in the interior of the earth, to those which cause eruptions on its surface, and by the pressure of elastic vapours, give rise to burning streams of lava that flow from open fissures.

The same powers that raised the chains of the Andes and the Himalaya to the regions of perpetual snow, have occasioned new compositions and new textures in the rocky masses, and have altered the strata which had been previously deposited from fluids impregnated with organic substances. We here trace the series of formations, divided and superposed according to their age, and depending upon the changes of configuration of the surface, the dynamic relations of upheaving forces, and the chemical action of vapours issuing from the fissures.

The form and distribution of continents, that is to say, of that solid portion of the Earth's surface which is suited to the luxuriant development of vegetable life, are associated by intimate connexion and reciprocal action with the encircling sea, in which organic life is almost entirely limited to the animal world. The liquid element is again covered by the atmosphere, an aerial ocean, in which the mountainchains and high plains of the dry land rise like shoals, occasioning a variety of currents and changes of temperature, collecting vapour from the region of clouds, and distributing life and motion by the action of the streams of water which flow from their declivities.

Whilst the geography of plants and animals depends on these intricate relations of the distribution of sea and land, the configuration of the surface, and the direction of isothermal lines, (or zones of equal mean annual heat,) we find that the case is totally different when we consider the human race the last and noblest subject in a physical description of the globe. The characteristic differences in races, and their relative numerical distribution over the Earth's surface, are conditions affected not by natural relations alone, but at the same time and specially, by the progress of civi

lisation, and by moral and intellectual cultivation, on which depends the political superiority that distinguishes national progress. Some few races, clinging, as it were, to the soil, are supplanted and ruined by the dangerous vicinity of others more civilized than themselves, until scarce a trace of their existence remains. Other races again, not the strongest in numbers, traverse the liquid element, and thus become the first to acquire, although late, a geographical knowledge of at least the maritime lands of the whole surface of our globe from pole to pole.-HUMBOLDT.

FIGURE OF THE EARTH.

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Three methods have been employed to investigate the curvature of the Earth's surface, viz., measurements of degrees, oscillations of the pendulum, and observations of the inequalities in the moon's orbit. The first is a direct geometrical and astronomical method, whilst in the other two, we determine, from accurately observed movements, the amount of the forces which occasion these movements, and from these forces we arrive at the cause whence they have originated, viz., the compression of our terrestrial spheroid. The comparison of eleven measurements of degrees, gives, according to the most strictly theoretical requirements, a compression of. In accordance with this calculation the polar radius of the earth is about miles shorter than the equatorial radius. The excess at the equator, in consequence of the curvature of the upper surface of the globe, amounts, consequently, in the direction of gravitation, to somewhat more than 4 times the height of Mont Blanc, or only 2 times the probable height of the Dhawalagiri, in the Himalaya chain. The lunar inequalities (perturbation in the moon's latitude and longitude) give, according to the last investigations of Laplace, almost the same result for the ellipticity as the measurements of degrees, viz., . The results yielded by the oscillations of the pendulum give on the whole a much greater amount of compression, viz., 5.

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1 The general rotundity of the Earth is here taken for granted; the arguments for it are drawn from the manner in which lofty objects appear or disappear in advancing towards or receding from them; from the fact of its circumnavigation; from the altered positions of the stars by movement on its surface; from the shape of its shadow on the Moon in eclipses, &c.-See Herschel's Astronomy, ch. i.

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