of motion, arising from the natural powers of gravity, elasticity, and the resistance of fluids. Whence he rises by the assistance of his own sublime geometry, to investigate the true forces of these powers in nature, and then from those forces demonstrates the other phenomena, particularly in settling the system of the heavens; he shows in the first book what are the genuine effects of central forces, in all hypotheses whatsoever that can be framed concerning the laws of attraction; then from Kepler's rules and other astronomical and geographical observations, he shows what the particular laws of attraction are in nature, and proves that this attraction is every where the same as the terrestrial gravity, by the force of which all bodies tend to the sun, and to the several planets. Then from other demonstrations, which are also mathematical, he deduces the motion of the planets, the comets, the moon, and the sea." Biog. Brit. Article Newton.

Improving upon the discoveries of Kepler, Newton demonstrated that the planets were attracted towards the sun, as a common center; that the force of this attraction was reciprocally as the squares of their distances from this center; that they revolved in ellipses, having the sun in one of the foci, and that when bodies did so resolve in ellipses, the squares of . their periodic times must necessarily vary as the cubes of their mean distances. See Vince's Astronomy, vol i, p. 100.

Persevering with undiminished ardour in his philosophical labours, he determined the true figure of the earth; and the travels of the French academicians to measure the unequal length of a degree at the equator and the poles, served only to verify, by actual obser

vation, the problem which he had solved in his closet. His speculations were not confined to our planetary system; for he extended them to all the stars that shine in the vast expanse of heaven. Every one, from analogy, was determined to be the centre of an harmonious system, subject to the same general laws as that of the sun.

In other branches of philosophy, he was greatly indebted to the previous investigations of others for a foundation, whereon to build his improvements; with respect however to his researches into the nature and properties of light, he was the author of a new and beautiful theory. He calculated its velocity, as it flows in perpetual and rapid streams from the sun. He instructs us, that it is diffused through our planetary system, while its heat is diminished in proportion to the square of the distance from its source. He scrutinized its various properties, as well as the laws of its motion. By the aid of a triangular prism of well polished glass, he analysed its rays, and saw the rich and brilliant display of the seven primogenial colours of which light is composed. These colours appeared not strongly contrasted with each other, but melted by gentle gradations into the neighbouring tints.

"He from the whitening undistinguished blaze
Collecting every ray into his kind,

To the charmed eye educed the gorgeous train
Of parent colours. First the flaming red
Sprung vivid forth; the tawny orange next;
And next delicious yellow; by whose side
Fell the kind beams of all refreshing green,
Then the puree, that swells autumnal skies;

Ethereal play'd; and then of sadder hue
Emerged the deepened indigo, as when
The heavy skirted evening droops with frost.
While the last gleaming of refracted light
Died in the fainting violet away.

Thomson's Poem to the Memory of Sir I. Newton.

His active mind sought relaxation in researches into remote times: he applied astronomy to rectify the computations of chronology, and succeeded in referring the most remarkable transactions, that were obscured by remote antiquity, to the most probable periods of time. See the History of the Jews, vol. i. By the unwearied exercise of close and patient meditation upon deep mathematical learning, and a series of correct and accurate experiments, he carried his discoveries into the recesses of nature, and developed the sublime and simple laws of matter and of motion. That his insight into the constitution of the universe did not extend to any greater length, seems not so much to be attributed to the narrowness of his own capacity, as to the imperfection of human nature itself. He discovered the plain vestiges of the Creator in his works; and, filled with the most sublime conceptions of his power, wisdom, and goodness, he ever bowed with reverential awe at the mention of his adorable name. Genius, science, industry, and diffidence, combined to form this great philosopher; and his various exertions, as successful as they were transcendent, displayed at once the depth, the extent, and the energy of his intellectual powers. Commencing his researches with plain and easy principles, and terminating them with the most sublime discover ́ies, the progress of his mind was like the mystic ladder in the vision of the patriarch, which reached from earth even to the footstool of God. It reflects no in

considerable credit upon the understandings of men to comprehend the extent of his discoveries; and it is no small happiness to every person of a scientific turn of mind, to live subsequent to the age which he irradiated by his genius. And how preeminent is the glory of Britain to enroll in the list of her enlightened sons, the man who may be denominated the great interpreter of the laws of nature, and the brightest luminary of science!

Newton, with the diffidence of one, who was truly sensible of the limited powers of the human mind, advanced with slow and steady pace along the road of experiment, and ascended from certain effects, ascertained upon earth, to obscure causes, which were concealed in heaven. With an ardent and penetrating eye he looked abroad upon nature, discovered her genuine character, and, always acting under the control of a cautious and solid judgment, established no principles, which were not perfectly consistent with her real constitution. He thought it not beneath thedignity of his philosophical character to remark the slightest effects, aimed at certainty in particular pursuits; and had the merit, the glory, and the happiness, to be in every pursuit successful.

So justly does the genius of Newton claim a conspicuous place in every discussion of mathematical subjects. Still however we are not so far dazzled by the lustre even of his name, or astonished by the extent and the variety of his discoveries, as to think that the works of nature are solely to be viewed through the medium of theorems and calculations. The works of the great Creator are not confined to abstract considerations of numbers and measures, as the sole criteria of their excellence. The sublime productions

of Almighty power, the sun shining in meridian glory, the moon pouring her mild light upon the earth, the ocean rolling its vast floods, and the beautiful colours which diversify all objects, charm the heart, and please the fancy, by their external appearance, at least as much as an inquiry into their laws, nature, and constitution can satisfy the understanding..

CHAPTER IV.

THE WORKS OF NATURE.

IT is the glorious privilege of man, while other animals are confined within the limits which instinct has prescribed, to carry his observations beyond his own immediate wants, and to contemplate the universe at large. He extends his inquiries to all the objects which surround him, and exercises his judgment, and informs his understanding, by ascertaining their nature properties, and uses. In the various branches of the mathematics, in the abstract speculations of metaphysics, or in searching the records of history, he is solely intent upon the operations of his own mind, or the actions of himself and his fellow creatures: but in the study of nature, he examines every object presented to his senses, and takes a general survey of the wide and interesting prospects of the creation. The earth he treads, the ocean he crosses, the air he breathes, the starry heavens on which he gazes, the mines and caverns he explores, all present to him abundant materials for his researches. And when thus employed, he is engaged in a manner peculiarly