(Ludovicus), the contemporary and friend of Erasmus, was a native of Valencia in Spain. Though well trained in all the subtleties of the scholastic philosophy at Paris, he had the good sense to discover its futility, and diligently applied himself to more useful studies. At Louvain he undertook the office of a preceptor, and exerted himself with great ability and success in correcting barbarism, chastising the corruptors of learning, and reviving a taste for true science and elegant letters. Erasmus, with whom he lived upon the footing footing of intimate friendship, speaking of Vives when he was only 26 years of age, says, that there was no part of philosophy in which he did not excel; and that he had made such proficiency in learning, and in the arts of speaking and writing, that he scarcely knew his equal. He wrote a commentary upon Augustine's treatise De Civitate Dei, which discovers an extensive acquaintance with ancient philosophy. Henry VIII. of England, to whom he dedicated this work, was so pleased with it, that he invited the author to his court, and made him preceptor to his daughter Mary. Though he discharged his office with great fidelity, yet in consequence of his opposition to the king's divorce, he fell under his displeasure; and it was not without difficulty that he escaped to Bruges, where he devoted the remainder of his days to study. He died in the year 1537, or, according to Thuanus, in 1541. With Erasmus and Buddeus he formed a triumvirate of literature which did honour to the age. He wrote De Prima Philosophia, "On the First Philosophy;" De Explicationibus Effectionum, "On the Explanation of Effects;" De Censura Veri, "On the Test of Truth;" De Initio, Setti, et Laudibus Philosophiae, "On the Origin, Setts, and Prais of Philosophy;" and De Corruptione Artium et Tradendis Dignitatis, "On the Corruption of Science, and on Education." These writings, of which the two last are the most valuable, discover great strength of judgment, an extensive knowledge of philosophy, much enlargement of conception, uncommon sagacity in detecting the errors of ancient and modern philosophers, particularly of Aristotle and his followers; and, in fine, a mind capable of attempting things beyond the standard of the age in which he lived. To all this he added great perspicuity and elegance of style, not unworthy of the friend of Erasmus.

ULTRAMARINE is a very fine blue powder, almost of the colour of the cornflower or blue bottle, which has this uncommon property, that, when exposed to the air or moderate heat, it neither fades nor becomes tarnished. On this account it is used in painting; but it was employed formerly for that purpose much more than at present, as salt, a far cheaper article, was not then known. (See Cobalt, in this Suppl.) Ultramarine is made of the blue parts of the lapis lazuli, by separating them as much as possible from the other coloured particles with which they are mixed, and reducing them to a fine powder. The real lapis lazuli is found in the mountains of that part of Turkey called Bucharia, which extends eastward from the Caspian Sea, and particularly at Kalab and Budukchou. It is sent thence to the East Indies, and from the East Indies to Europe. Good ultramarine must be of a beautiful dark colour, and free from sand as well as every other mixture. It must unite readily with oil; it must not become tarnished on a red-hot tile or plate of iron, and it ought to dissolve in strong acids, almost like the zecolite, without causing an effervescence. In the year 1763, an ounce of it at Paris cost four pounds sterling, and an ounce of cendre d'outremer, which is the refuse, two pounds. The basis of this colour was long suspected to be copper, but the experiments of Margraff showed that it was iron, in some unknown state of combination. New light has been thrown on this subject by Moreau, who has discovered that felsnite loaded with iron, when decomposed by carbonaceous matter, yields a blue sulphuret of iron of equal permanency with the true ultramarine.

At present, smalt of a good colour is often purchased at a dear rate and substituted for ultramarine; and it is found that the colour of this preparation of cobalt is more durable in the fire than even that of the lapis lazuli. For the analysis of lapis lazuli, see Mineralogy, No. 69. Suppl.

VORTICES of Des Cartes are now justly exploded; but being the fiction of a very superior mind, they are still an object of curiosity, as being the foundation of a great philosophical romance. According to the author of that romance, the whole of infinite space was full of matter; for with him matter and extension were the same, and consequently there could be no void. This immensity of matter he supposed to be divided into an infinite number of very small cubes; all of which, being whirled about upon their own centres, necessarily gave occasion to the production of two different elements. The first consisted of those angular parts which, having been necessarily rubbed off, and ground yet smaller by their mutual friction, constituted the most subtle and moveable part of matter. The second consisted of those little globules that were formed by the rubbing off of the first. The interstices between these globules of the second element were filled up by the particles of the first. But in the infinite collisions, which must occur in an infinite space filled with matter, and all in motion, it must necessarily happen that many of the globules of the second element should be broken and ground down into the first. The quantity of the first element having thus been increased beyond what was sufficient to fill up the interstices of the second, it must, in many places, have been heaped up together, without any mixture of the second along with it. Such, according to Des Cartes, was the original division of matter. Upon this multitude of matter thus divided, a certain quantity of motion was originally impressed by the Creator of all things, and the laws of motion were so adjusted as always to preserve the same quantity in it, without increase, and without diminution. Whatever motion was lost by one part of matter, was communicated to some other; and whatever was acquired by one part of matter, was derived from some other; and thus, through an eternal revolution from rest to motion, and from motion to rest, in every part of the universe, the quantity of motion in the whole was always the same.

But as there was no void, no one part of matter could be moved without thrusting some other out of its place, nor that without thrusting some other, and so on. To avoid, therefore, an infinite progress, he supposed that the matter which any body pushed before it rolled immediately backwards to supply the place of that matter which bowed in behind it; as we may observe in the swimming of a fish, that the water which it pushes before it immediately rolls backwards to supply the place of what flows in behind it, and thus forms a small circle or vortex round the body of the fish. It was in the same manner that the motion originally impressed by the Creator upon the multitude of matter necessarily produced in it an infinity of greater and smaller vortices, or circular streams; and the law of motion being so adjusted as always to preserve the same quantity of motion in the universe, those vortices either continued... Vortices, for ever, or by their dissolution gave birth to others of the same kind. There was thus at all times an infinite number of greater and smaller vortices, or circular streams, revolving in the universe.

But whatever moves in a circle is constantly endeavouring to fly off from the centre of its revolution. For the natural motion of all bodies is in a straight line. All the particles of matter therefore, in each of those greater vortices, were continually pressing from the centre to the circumference, with more or less force, according to the different degrees of their bulk and solidity. The larger and more solid globules of the second element forced themselves upwards to the circumference, while the smaller, more yielding, and more active particles of the first, which could flow even through the interstices of the second, were forced downwards to the centre. They were forced downwards to the centre notwithstanding their natural tendency was upwards to the circumference; for the same reason that a piece of wood, when plunged in water, is forced upwards to the surface, notwithstanding its natural tendency is downwards to the bottom; because its tendency downwards is less strong than that of the particles of water, which, therefore, if one may say so, press in before it, and thus force it upwards. But there being a greater quantity of the first element than what was necessary to fill up the interstices of the second, it was necessarily accumulated in the centre of each of these great circular streams, and formed there the fiery and active substance of the sun.

For, according to that philosopher, the solar systems were infinite in number, each fixed star being the centre of one; and he is among the first of the moderns who thus took away the boundaries of the universe: even Copernicus and Kepler, themselves, have confined it within what they supposed the vault of the firmament.

The centre of each vortex being thus occupied by the most active and moveable parts of matter, there was necessarily among them a more violent agitation than in any other part of the vortex, and this violent agitation of the centre cherished and supported the movement of the whole. But among the particles of the first element, which fill up the interstices of the second, there are many, which, from the pressure of the globules on all sides of them, necessarily receive an angular form, and thus constitute a third element of particles less fit for motion than those of the other two. As the particles, however, of this third element were formed in the interstices of the second, they are necessarily smaller than those of the second, and are therefore, along with those of the first, urged down towards the centre, where, when a number of them happen to take hold of one another, they form such spots upon the surface of the accumulated particles of the first element, as are often discovered by telescopes upon the face of that sun which enlightens and animates our particular system. Those spots are often broken and dispelled by the violent agitation of the particles of the first element, as has hitherto happily been the case with those which have successively been formed upon the face of our sun. Sometimes, however, they encrust the whole surface of that fire which is accumulated in the centre; and the communication betwixt the most active and the most inert parts of the vortex being thus interrupted, the rapidity of its motion immediately begins to languish, and can no longer defend it from being swallowed up and carried away by the superior violence of some other like circular streams; and, in this manner, what was once a sun becomes a planet. Thus the time was, according to the system, when the Moon was a body of the same kind with the sun, the fiery centre of a circular stream of ether, which flowed continually round her; but her face having been encrusted over by a congeries of angular particles, the motion of this circular stream began to languish, and could no longer defend itself from being absorbed by the more violent vortex of the earth, which was then, too, a sun, and which chanced to be placed in its neighbourhood. The moon therefore became a planet, and revolved round the earth. In process of time, the same fortune, which had thus befallen the moon, befell also the earth; its face was encrusted by a grofs and inactive substance; the motion of its vortex began to languish, and it was absorbed by the greater vortex of the sun: but though the vortex of the earth had thus become languid, it still had force enough to occasion both the diurnal revolution of the earth, and the monthly motion of the moon. For a small circular stream may easily be conceived as flowing round the body of the earth, at the same time that it is carried along by that great ocean of ether which is continually revolving round the sun; in the same manner, as in a great whirlpool of water, one may often see several small whirlpools, which revolve round centres of their own, and at the same time are carried round the centre of the great one. Such was the cause of the original formation and consequent motions of the planetary system. When a solid body is turned round its centre, those parts of it which are nearest, and those which are remotest from the centre, complete their revolutions in one and the same time. But it is otherwise with the revolutions of a fluid: the parts of it which are nearest the centre complete their revolutions in a shorter time than those which are remoter. The planets, therefore, all floating in that immense tide of ether which is continually setting in from west to east round the body of the sun, complete their revolutions in a longer or a shorter time, according to their nearness or distance from him.

This bold system was eminently fitted to captivate the imagination; and though fraught with contradictions and imposibilities, attempts have been made to revive it, even in this country, under different names. All those systems which represent the motions of the heavenly bodies as being the effect of the physical agency of ethers, of air, of fire, and of light, of which the universe is conceived to be full, labour under the same difficulties with the Cartesian hypothesis; and very few of them, if any, are to neatly put together. It is surely sufficient, however, to demolish this goodly fabric, barely to ask how an absolute infinity of matter can be divided into cubes, or any thing else? how there can possibly be interstices in a perfect plenum? or how in such a plenum any portion of matter can be thrust from its place?