Page:A biographical dictionary of eminent Scotsmen, vol 5.djvu/225

Rh 1671. He received the rudiments of education in the schools of his native city, and remained at the Edinburgh university until he was enabled to take the degree of master of arts. He early displayed a genius and predilection for mathematics, and had the good fortune to study the science, along with the Newtonian system of philosophy, under Dr Gregory. When, in the year 1694, Gregory went to try his fortune in England, Keill followed him, and contrived along with him to find admission to Oxford, where he held one of the Scottish exhibitions in Baliol college. Keill made his first appearance before the scientific world in his "Examination of Dr Burnet's Theory of the Earth, together with some remarks on Mr Whiston's new Theory of the Earth," published at Oxford in the year 1698. Any "Theory of the Earth," or account of its formation and state, in anticipation of the discovery of facts to support it, always formed a fruitful subject of debate; but Burnet's Theory afforded more ample field for censure than any other which pretended to support from the enlightened doctrines of modern philosophy. The grand outlines of his theory were of themselves sufficiently imaginative, and their effect was increased by the curious speculations with which he filled up the minor details of his edifice. He supposes the earth to have been originally a heterogeneous mass of fluid matter, of which the heavier portions fell to the centre, forming there a dense body, surrounded and coated by lighter bodies, while the water the lightest of all the heterogeneous mass, remained on the outside of the whole. The air and other celestial fluids floated round this body: while between it and the water was gradually formed a coat of unctuous or oily matter, higher than water. Upon this unctuous coat, certain impure particles which had at first been mingled with the air, descended, and floating about covered the surface, forming a shell over the water, which became the crust of the earth. The crust thus formed was level and uniform, without hill or vale; so it remained for about sixteen centuries, until the heat of the sun having cracked it in divers places, the water rushed forth, causing the general deluge. This water found, however, a means of partially subsiding, betwixt the broken masses of the crust, and thus leaving the globe in the state of ocean, hill, and valley.

Keill, who, besides being a man of accurate science, was a person of clear good sense and critical acumen, saw clearly the evil done to science, by the admission of suppositions which have a fully greater chance of being wrong than of being right, while the richness of the doctor's imagination, and the poetic beauty of his language and illustration, did not protect his principles from a subjection to the strict rules of logic. Keill's book is full of the clear argumentation of a man who is rather formed to correct and check the discoveries of others, than to allow his invention to stray so far as to make any of his own. He occasionally condescends to use demonstration, while, well knowing that there may be positions against which the gravity of an argument is misapplied, he makes very frequent use of sarcasm, a power of which he is an accomplished and apt handler. Most of the vigour of the attack is derived from the manner in which the different parts of the theory are found inconsistent with each other, without any very extensive reference to other authority. "After this fashion," says Keill, after giving an outline of Burnet's first formation of the earth, "has the theorist formed his antediluvian habitable world, which doth not much differ from the Cartesian method of making the earth: only Des Cartes, being somewhat wiser than the theorist, would not allow the outward crust, within whose bowels the waters were shut up, to be a habitable earth, knowing well that neither man nor beast could live long without water. But he made the crust first be broken, and the waters flow out, before he placed any inhabitants on it.