confers adaptation on whatever it conjoins. We can seek no criterion of fitness in the nature of things, but must ultimately refer all rule and standard to the origin of things. To imagine a difficulty, is to imagine an independent existence, to the nature of which, in the contemplation of endowing with attributes, intention and design must conform; in which supposition, certainly, the idea of possibility and impossibility is admissible, though we may not be entitled to pronounce thereon; but when we allow that substance and power are equally the result of creating will, all ground for argument on natural incongruity and impossibility, is given up, seeing that the nature of things is made to be what it is, and that congruity can have no other criterion, can be referred to no higher source, than the will which constituted it. Metaphysical subtleties, therefore, are utterly inadequate to enable us either to affirm or deny, by à priori reasoning, concerning any powers which any substance can support; and when we would reason on things as we find them, our entire ignorance of their essence, precludes alike all doginatisin on the subject. I am aware- -what, indeed, has been already mentioned-that Locke regards matter as being essentially inert, as being only passive, and spirit alone as being active; but if substance in any case is, as he allows, quite unknown to us, we are by our ignorance of its nature rendered incompetent to perceive an incompatibility with the attribute of power, in one order of being more than in another. Nay, the very distinction into orders or kinds of being, rests on and is determined by the different powers which they possess, and not on any thing which we know of their substance. That the difference in their attributes is immense, is very apparent; that the difference extends in an equal degree to their essences, is conjectural, but highly probable. The power which belongs to intelligent natures, is of a higher order than that which it is contended may be the attribute of matter. It has perma ⚫ These terms were not used by Locke, merely in the sense of saying, what is sufficiently obvious, that matter is devoid of an originating self-moving principle, but to assert that it is so essentially powerless, that any appearances which may indicate a contrary opinion, must be referred to its being acted upon, or to an action through it by a more potential nature, of which alone activity is an attribute. nent authority over the latter, ruling and modifying it in its various operations. It has also its own peculiar province, and its manifestation, in whatever manner, is not of necessity but springs forth from volition. It works vast changes in the face of nature, being a creator of differences if not of things. Material power, on the other hand, has a constrained action, and all its operations are inevitable consequences of its original constitution. The changes and fresh combinations which are wrought out by it are also vast and incessant, but they have no immediate origin; they own no spontaneous, no irregular course, they deviate not from the path in which they were first appointed to run. If, then, a created substance claims in its own right, and for its own proper keeping and developement, the superior power, what difficulty is there in admitting that another created substance can be endowed, in its own right also, with power of an inferior kind, of a necessitated, blind, and unerring action, if the Divine Author of both should see fit. These things are only equally wonderful and mysterious, for we have no ground on which we can rest a comparison, but if any difference be made, we ought more readily to allow the existence of the lower order of power, which distinguishes unwilling, unintelligent nature, On these several grounds, therefore, I consider the doctrine of the existence of matter, unaccompanied with powers that are properly and essentially its own, to be untenable. 2. Let us now advert to the opposite doctrine of power without substance. This doctrine denies the validity of the inference previously mentioned, of the necessary existence of the latter as a substratum for the former. This is, in other words, the notion of the independent existence of properties; for, as I have before observed, power is so called when spoken of, not abstractedly, but in reference to the kinds of perception by which it makes itself manifest to us. Now to conceive of properties in this manner is very difficult if not impossible, and is alike alien to our language as to our thoughts, the one being the result of the other. This will appear if we speak, for instance, of motion, and ask what it is the motion of ?—and we must answer, of extension, of solidity, and of the other properties, including even mo tion itself, for it must be as true of this property as of any other. We must not answer-of matter, for that would be to admit the something of which motion is a property. If we say that motion, extension, &c. are perceptions of the mind, then we admit they have no existence external to ourselves, and we enter upon another doctrine. We have, in the experience of our own minds, a conviction of the existence of something distinct and apart from our powers, and which preserves its own identity, amidst the fluctuations in extent and intensity to which those powers are liable. We are as confident as we can be of any thing, that we are not, as Hume would persuade us, a mere bundle of perceptions. We are conscious that sounds do not hear sounds, nor see colours, and that happiness is not percipient of misery, nor action of passion; but that a distinct principle, or being rather, is the common subject of these perceptions, and which exists in all vicissitudes the same in essence, whole and unimpaired. Now it is from these considerations, that we are led in an equally irresistible manner to conclude, that the powers which are external to us, are likewise connected with something distinct from themselves; that they are not a congeries of things, without a common bond to hold them in one identity; and that they are not the interchangeable properties of themselves, nor of each other-motion being neither the property of motion, nor of extension, nor of solidity, nor of any other quality, nor of an aggregate of qualities. Mr. Exley is, however, of opinion, that 66 power constitutes the very essence of matter." This if it be not idealism, is at least the doctrine of the immaterialism of the universe, according to the notion which is generally entertained of materiality. But if we admit the existence of a Deity, and that “ power belongeth to Him alone;" and more especially, if we assert with Clarke, Dugald Stewart, and the most eminent moral philosophers, in the decisive language of a distinguished living divine-"that all events in the natural universe are the immediate effects of the Divine agency," and at the same time affirm that matter is mere power, we do unequivocally advance the doctrine of idealism, and become at once the disciples of Berkely, acknowledging with him the direct and immediate presence and action of the Divine Being, in accordance and in connexion only, with instituted and im mutable laws. We make, in short, the sole cause in external nature to be that which is supreme. On the supposition, that " power constitutes the very essence of matter,” how strange must be our language, for instance, concerning attraction. We must say, that the power of attraction attracts another power of attraction. It is to me inconceivable that this force can have only a similar force for its object, without destroying all distinction between action and passion; or that it can have an object to act upon, without it has a subject to act from, and be reciprocally under similar influence, and therefore of a similar kind. If, as Mr. Exley would probably reply, we know nothing more of nature than of force acting against force, and make no further inference concerning it, we can only have a discernment of it as force; and herein certainly, that is, in our own minds, is found an object for force, but herein as certainly, it only finds an existence, and thus again all things are resolved into perception. Under this idea, force assuredly may be supposed to act against and modify force, both the operations and the agents being in the mind-like the working out of a geometrical truth by a mental demonstration-but as assuredly, though the truth may be as certain, they will be equally ideal, and we must substitute things for powers, or at least conceive of them in addition, if we would not be satisfied short of an external reality. Mr. Exley, however, does not make it an indispensable principle in his theory of physics, that matter is merely a force; but he allows the reader to imagine, if he chooses, the existence of indefinitely small solids at the centre of those spheres of attraction and repulsion which constitute his atom of matter. It is well known that Newton was of opinion that "God, in the beginning, formed matter in solid massy, hard, impenetrable particles ;" and there is an expression of his, which, being unlimitedly advanced, shows that he could not even conceive of power or properties in reference to matter, without something wherein they should subsist. He even asserts the same in reference to the Deity, and ventures to decide a question which ought to be unapproachable. With the confidence more characteristic of the metaphysician than Sir, I send you a sketch and description of an apparatus for procuring vacuum, which I have lately invented, and which I have called the hydropneumatic pump. Should you deem the communication worthy of notice, I shall feel obliged by your giving it insertion in one of your early Numbers; and have the honour to remain, Sir, Your most obedient servant, March 17, 1835. Description. The apparatus consists of two stout glass cylinders A and B; the one, A, may be termed the condenser; the other, B, the receiver: the former is fixed to the stand G, the latter is moveable, for the purpose of experiment. These cylinders are fitted with two upright brass necks, Id; that of A is furnished with a valve e, opening upwards into the atmosphere, and that of B is bent at a right angle, so as to screw at h, on the cross-branch ƒ, from the other neck, and thus to form with it an entire air-tight tube, which tube has a valve, c, opening outwards, by a spring or otherwise, into the neck I. The cylinder A is farther furnished with a tube K, for supplying it with water; it passes through the stand G, enters A at O, and terminates in F. This tube has a cock L, or other similar contrivance, for admitting or intercepting the fluid, as may be requisite; and near to this in A, as shown by the dotted circle M, is another cock for withdrawing the water from A, when necessary, each of these cocks being both air and watertight. The pump is put into operation in the following manner-the receiver B having been previously removed for the sake of experiment, by unscrewing its neck dab, and afterwards replaced upon the standing, or rather upon a receiverplate attached to it. First, the cock L being opened, and that at M shut, water is poured or admitted in any other manner into the pipe K, and flows from it into the cylinder A. As it rises it condenses the air within A; the valve e is consequently opened, and when it reaches the height indicated by the dotted line xy, it has expelled through e nearly all the air which the cylinder contained. The valve e having again fallen, the cock L is shut so as to cut off the supply of water to A. Now this cock, as well as that at M, being air-tight, and the former having, moreover, above it, a column of water, the level of which, by the laws of fluids, corresponds with the line xy, it necessarily follows, upon opening the cock at M, so as to allow the water in A to escape, and again shutting it (taking care, of course, not to admit any air from without to pass through it into A), that a vacuum will be left within A; consequently, the air in the receiver B will rush through the cross-tube f, and valve c, to restore the equilibrium, and will thus become rarefied; this effect will, indeed, take place as soon as the air in A assumes a less density than that in B. Further, as the air which A now contains, and which, it is almost superfluous to observe, possesses the same density with that in B, cannot pass back to B, for the valve c is now shut, it also follows, that, if the cock L be again opened and water readmitted to A, it will be, as before, con densed, and ultimately driven out at e; and, as a consequence, upon a second time opening and shutting the cock at M, another vacuum will be created in A; this will, likewise, be occupied by the air from B, which becomes, of course, still more rarefied; and these operations being repeated, the air in B will, at length, be so far exhausted, as to constitute an almost perfect vaccuum. I have not made any reference to the relative size of the cylinders, this being a point of but minor importance. I may, however, observe, it is advisable that A should be more capacious than B (in proportion, for instance, by diameter, of 14, or 1 to 1); because, on the withdrawal of the water, the vacuum within A, and consequent rarefaction in B, will be the greater. On the other hand, it is evident, that, if A be made enormously large, it will not only require a considerable quantity of water for its supply, and a long period to fill; but the whole machine will, thereby, be rendered extremely unwieldy and inconvenient. It may, too, perhaps, be as well to state, that, in order to economise the water as much as possible, it may be conducted as it flows from the cock at M, by means of a pipe or otherwise, to a vessel appropriated for its reception, from which it may be again transferred to the cylinder A when required. W. H. O. MAP-PRINTING-MURRAY'S ENCYCLO PÆDIA OF GEOGRAPHY. Sir, It seems to have become quite the fashion of late years with authors and booksellers, whenever maps are required to illustrate their works, to go to the very extreme of shabbiness in getting them up. Even the west-end autocrat of the trade, "absolute John " himself, with all his aristocratic fastidiousness, does not blush to print the maps in Washington Irving's" Columbus," and other books of similar standard description, on a sort of blue tissue-paper, so wretchedly thin that the water-mark shows out with a distinctness vying with that of the engraved lines. Such miserable ultra-economy as this is quite inexcusable: we can put up with a black map, with the letters on a white ground, in the Penny "Guide to Knowledge," when we reflect that it is still, though not so elegant, nearly as useful as a copper-plate in the usual style, and that it is the time and labour saved, by the reversal of the usual process, which enable the proprietors to let us have a map of London for a mere trifle. But what saving of any consequence can be effected by the substitution of a half-sheet of blotting-paper for one of a decent quality, in the getting-up of a handsome volume ? Mr. Murray, and other delinquents on the same score, should "reform it altogether." Among other frugal novelties in map. ping, a new method has been introduced of composing a sort of letter-press map, with a very little assistance from the wood-engraver. This answers pretty well for plans of forts and harbours, &c., in such works as the "Penny Cyclopædia," for instance, where elegance of appearance is not of much consequence; but a complete failure is the consequence, whenever it is attempted to give a map of a large extent of country, or any thing else including a great number of objects and names, in this style; and in all cases it invariably has a very mean, paltry, and unhandsome effect. Yet, Mr. Editor, it is in this style that all the maps in Mr. Hugh Murray's latelypublished Encyclopædia of Geography are executed and miserable, indeed, is the effect produced. Surely, as this "Encyclopædia" was intended from the first to become a regular standard work, and to run through a "number without number" of editions, the proprietors might, without incurring the imputation of extravagance, have gone to the expense of having a decent set of maps engraved on steel or copper, instead of presenting the reader with a "complete atlas," which he soon finds to be worse than useless-an atlas in name, and in name only. 66 It would, indeed, be ridiculous to refer to any of these maps for the elucidation of the text. For one thing, owing to the manner of their getting-up, they present to the eye, at the first glance, a chaotic mass of lines and figures, with out order or meaning, whilst a nearer inspection shows only an unaccountable medley of blunders and mistakes, of all sorts, sizes, and descriptions. And yet, with all this, the Preface leads us to expect the most scrupulous correctness; the Editor even calls particular attention to this branch of his work, and affirms that it has cost him considerable pains. "The maps," he observes, "which are SO numerous as to form a complete atlas, have been executed from drawings by Hall, and having been care fully revised by the Editor, they will, it is hoped, be found to be accurate, and to include all the most recent discoveries." Let us see how this assertion is kept in countenance by the map of no more remote and inaccessible a portion of the globe than "The British Islands." The attention is naturally at first drawn to the capital, and here a fine proof of the "careful revision" of the Editor stares the observer in the face at the first glance. "London" is duly placed on the north bank of the Thames, but bounded by two other rivers, one at the eastern, and the other at the western extremity the former, of course, may be supposed to represent the Lea, but the latter exists only in the imagination of Mr. Hall, who drew on the Editor who 66 : carefully revised" this most accurate of maps. After this, the omission of two such obscure places as Westminster and Southwark (and entirely omitted they are), may probably seem but a trifle; but it is certainly going too far to remove Plymouth to the Cornish side of the estuary of the Tamar, and thus place one of the most extensive of our seaports not only far out of its proper position, but even out of the county to which it belongs. "Chester" is almost as badly served; it is not placed out of Cheshire, but it is removed from the banks of the Dee to those of the Mersey, with as little ceremony as Plymouth is made to change sides. It is quite evident from these two or three glaring instances alone, that this carefully-constructed map has been put together in the most careless manner; and a further inspection of it only serves the more fully to confirm that opinion. There is one circumstance, indeed, which operates strongly to shield its innumerable blunders from observation. The names of the towns, &c., are not given on the map itself, but in a separate page of letter-press, to which reference is made from the map by means of figures -a method which answers no purpose so completely as that of perplexing the reader, especially as the multiplicity of objects (the whole British Islands on an |