ing themselves under different combinations with the material mass, and giving birth to many of its most extraordinary properties and phænomena.

The question is entered upon at some length by Professor Berzelius, in his " Explanatory Statement," published in the Memoirs of the Academy of Stockholm for 1812, in which he endeavours to support the probability that the electric fluids and caloric are material, as well as the fluid of light; but to do this he is compelled to alter the common definition of matter, and to contend that matter does not necessarily possess gravitation or aggregation.*

The materiality of light has been attempted to be proved by its effects on solutions of muriate of ammonia and prussiate of potash, when placed in a situation to be crystallised. The crystallisation of these salts may be directed at pleasure by the introduction of light at one or the other side of the vessels containing such solutions. Camphor displays a like affinity for light. All this, however, shows merely that light possesses an influence of some kind; but it by no means establishes that such influence is a material one.†

Is it enquired to what important point these abstruse speculations lead? I may reply, among others, to the following:

First, to a probability, if not to a proof, that matter, under peculiar modifications, is capable of making an approximation to something beyond itself, as ordinarily displayed; and hereby of becoming

*See Nicholson's Journal, vol. xxxiv. p. 164, 165.

+ See Accum's Elements of Crystallography, and Tilloch's Phil. Mag. vol. xli. p. 367.

fitted, whenever necessary, for an intercourse and union with an immaterial principle.

And, secondly, to a clearer view of the coincidence of natural phænomena with one of the most glorious discoveries of revelation. For notwithstanding that matter, under every visible shape and texture, is at present, in a greater or less degree, perpetually changing and decomposing, the moment we perceive that this is not a necessary effect, dependent upon its intrinsic nature, but a beneficial power superadded to it for the mere purpose of rendering it a more varied and more extensive medium of being, beauty, and happiness-the moment we find ground for believing, that in its elementary principles it is essentially solid and unchangeable, and that even in many of its compounds it is almost as much exempted from the law of change-we are prepared to contemplate a period in some distant futurity, in which, the great object for which it has been endowed with this superadded power being accomplished, the exemption may extend equally to every part and to every compound: a period in which there will be “new heavens and a new earth," and whatever is now corruptible will " put on incorruption."

But what, after all, is matter in its elementary principles, as far as we are capable of following them up? Can it be divided and subdivided to infinity? or is there a limit to such divisibility, beyond which the process cannot possibly proceed? and if so, are the ultimate bodies into which it is capable of dissolving still susceptible of developement, or, from their attenuation, removed beyond all power of detection?

These are questions which have agitated the

world in almost all ages, and have laid a foundation for a variety of theories, of too much consequence to be passed over in a course of physical investigation.

The tenet of an infinite divisibility of matter, whether in ancient or modern times, appears to have been a mere invention for the purpose of avoiding one or two self-contradictions supposed to be chargeable upon the doctrine of its ultimate and elementary solidity; but which, I much fear, will be found to have given birth to far more self-contradiction than it has removed. The mode of reasoning, however, by which this tenet was arrived at in ancient Greece, was essentially different from that by which it has been arrived at in our own day.

It being, as we observed in our last lecture, an uncontroverted maxim among all the Greek philosophers, of every sect and school whatever, that nothing could proceed from nothing, matter was of course conceived to have existed eternally, or it could not have existed at all. But it appeared obvious to most of them, that matter is as certainly unintelligent as they conjectured it is certainly eternal. The existence of intelligence, however, is still more demonstrable throughout nature than the existence of matter itself; and hence such philosophers were driven to the acknowledgment of an intelligent principle distinct from a material substance; and from the union of these two powers they accounted for the origin of the world: matter being merely passive and plastic, and put into form and endowed with the qualities and properties of body by the energy of the intelligent agent. But, if form and corporeal properties have been com

municated to it, it must, before such communication, and in its first or primal state, have been destitute of form; and that it was thus destitute is incontrovertible, continued the same schools of philosophy, because form presupposes the existence of intelligence, and must be, under every shape and modification, the product of an intelligent energy; for it is impossible that matter could have had a power of assuming one mode of form rather than another mode: since, if capable of assuming any kind, it must have been equally capable of assuming every kind, and, of course, of exhibiting intelligent effects without an intelligent cause, which would be utter

nonsense.

Such is the general train of reasoning that seems to have operated upon the minds of Pythagoras, Plato, and Aristotle, in impelling them to the belief that matter, in its primary state, to adopt the words of Cicero, in which he explains the Platonic doctrine, ❝is a substance without form or quality, but capable of receiving all forms, and undergoing every kind of change; in doing, which, however, it never suffers annihilation, but merely a solution of its parts, which are in their nature infinitely divisible, and move in portions of space which are also infinitely divisible." *

But if we abstract from matter form and quality, and at the same time deny it intelligence, what is there left to constitute it an eternal substance of any kind? and by what means could pure incorporeal intelligence endow it with form?

These difficulties are insuperable; and though

* Acad. Quæst. lib. i. cap. 8.

attempted to be explained in different ways by each of these philosophers, they press like mill-stones upon their different systems, and are perpetually in danger of drowning them. Pythagoras compared the existence of matter, in its primary and amorphous state, to pure arithmetical numbers, before they are rendered visible by arithmetical figures. "Unity," says he, " and one (the former of which he denominated monad) are to be distinguished from each other unity is an abstract conception resembling primary or incorporeal matter in its general aggregate; one appertains to things capable of being numbered, and may be compared to matter rendered visible under a particular form." So again, "Number is not infinite any more than matter; but it is nevertheless the source of that infinite divisibility into equal parts which is the property of all bodies."*

Numbers, however, were not more generally had recourse to by Pythagoras, to typify elementary matter under different modifications, than they are in the present day by the most elaborate chemists, to express its particular combinations : "As in all well-known compounds," observes Sir Humphry Davy, "the proportions of the elements are in certain definite ratios to each other, it is evident that these ratios may be expressed by numbers."+ In consequence of which they are so expressed in various places by himself, and by many French, Swedish, and English chemists; the hint having been

Anon. Photii, lib. c.

Nicomac. apud Phot. Themist. in Phys. lib. iii. sect. 25. p. 67. See also Enfield's Brucker, i.

b. ii. ch. 12. p. 383.

+ Davy, Elem. i. p. 112.