tuitively, or, if you please, instinctively, suggested.

By adopting the views which have been now unfolded, we shall cease to obtrude on either hand, those magisterial dicta which distinguish the opposite schools of dogmatism and assumption. We shall drop our pretensions to a knowledge of things which are beyond our reach; for what purpose, or by what party soever, it may be taught, and humbly confess, that we ourselves and all things around us are shrouded in impenetrable mystery. We shall ingenuously acknowledge, that we know nothing of essence, and that our true province, indeed our only ability, is to thread the labyrinth of the complicated effects of modifying powers, and to trace those powers truly, until we may arrive at their primal and simple forms. There we must for ever stop. The history and the progress of philosophy-the direction which its successful inquiries have taken the analogies of science, its universal tendencies to quantative results, and the peculiarities of the sensations themselves, all tend to create the belief, that the impressions referred to solidity, own no other cause than force. This conclusion would obtain a more ready assent, but that the mind clings to the notion that there is something else besides force, as being necessary to uphold it. Undoubtedly there is Something, though it is impossible for us even to conjecture what it can be, for the vision, therefore, hath not impressed the sense, nor the similitude thereof entered the mind. It is, however, to that something we are prone to attribute the actions upon us, instead of attributing them to the forces which it acts; and the mind, unsatisfied with the rude idea of force, eagerly avails itself of some of its own affections, wherewith to clothe that something to acquire a conception of i', to confer on it a substance and a form. But force, naked force, is all that by the present constitution of our nature, can pass from it to us. If the refined sensations of vision fail to disclose to us any thing of its essential nature, it is

I have here found an argument, or rather have analysed an operation of the mind, which enables me to reject with greater confidence the hypothesis of Berkeley, than I did in my former paper. I hope the argument will be found to be valid, notwithstanding that it has been often said by those who were not the friends of idealism, that it can. not be proved to be false.

in vain to imagine that the grosser sensations of touch will unfold to us more of its secrets. We are entitled to demand of a philosophy which shall teach us otherwise, its proof, that any of our sensations are coincident with, or characteristic of matter; we inquire, what right has it to turn these, our mental affections over to matter, and make them qualities thereof; and we require to know, what criterion it can point to, what guarantee it can offer; that as, in regard to some of them, it has confessedly gone astray, it is in its conclusions respecting solidity and extension, infallible.

The progress of knowledge has ever been in this direction-to narrow the bounds of legitimate inquiry, though, at the same time, to render investigations more definite and more exact. Already has philosophy moderated its pretensions to the point of acknowledging, that we know nothing concerning the efficiency of causes; and that our only object of discovery, is the invariable connexion of events. Why, then, should it persist any longer in the yet bolder pretension, that the nature of matter is open to observation, and that we do obtain an insight into the very source of the efficiency of causes, an access to the origin and fountain-head of power? Let us abandon this presumptuous thought, and thenceforward will cease those bitter animosities which have been engendered by differences of opinion on some points connected with this subject, and which it is lamentable to think, have arisen on both sides, from a misconception as to the limited extent of our reasoning and discerning powers. Doubtless the time will come, when we shall cease to insist that our knowlege of spirit and matter is so determinate, as to entitle us to decide, either on the one hand, that they are distinct and different essences; or, on the other hand, that the primary qualities of the latter, constitute the substance from which, in some of its modifications, result the attributes which are usually assigned to the former. In the day, when metaphysics shall have abandoned the high and long occupied ground of à priori reasoning--when it shall have come down from the region of pure intellect, and taken the humbler wa k so successfully trod in physics-the walk of observation and just in ́erences; in that

enlightened day of metaphysical discernment, we shall ingenuously acknowledge, that of aught beyond the effects and manifestations of power, we are in utter ignorance, and that the secret of its source and nature is inscrutable.

We have now taken a review of some of the consequences which logically and irresistably follow, from the doctrine involved in Mr. Exley's "Theory of Physics," and in many other theories and statements besides. The reader must have perceived, particularly from the tone of my latter remarks, that my own opinion is decidedly in favour of that doctrine. The truth is, that it is coincident with propositions which I have myself advanced in my former paper. I there affirm that "properties or qualities are certainly only the different manifestations of power, as severally operating upon us through our senses; and it is of this power only, in its varied forms, as affecting us through the several mediums of access, of which we can be sensible or have any discernment." This is fully equivalent to Mr. Exley's assertion, that "we know nothing of matter but by the forces which it exerts, and which, doubtless, constitute its nature," or rather its essential properties. The difference between us, lies in the circumstance merely that our respective premises have different conditions. The metaphysical truth is the same in both, and is, as I consider, absolutely certain, though its physical form is, I contend, only probable. Whilst, therefore, I am content to speak indefinitely of the primary powers of matter, because, confessedly, unacquainted with their form and law of action, Mr. Exley aspires to an exact knowledge of these arcana, and to give so definite a statement of the forces and their laws, as to be able to ground thereon a general theory of physics. Disagreeing as to the sufficiency of proof which he advances in behalf of his system, we agree in denying the validity of the distinction, between the primary and secondary qualities of matter, and in resolving all our knowledge of matter into a congnizance of its powers, as capable of impressing us with various sensations; or, in his own language, that matter is perceptible to man by means of its powers acting on the senses, which evidently in infinite wisdom, are adapted to receive the im

pression of these powers." Mr. Exley considers the principles of his system to be undeniable, whilst I can only regard them as uncertain and hypothetical, though not devoid of some probability. Nevertheless, this theory has a useful bearing on the metaphysical propositions and inferences which have been advanced, inasmuch as it shows, even in a physical aspect, the probability in the possibility, that certain original powers of matter excite those sensations which we usually attribute to qualities in bodies; and this it does, by pointing out their sufficiency for that purpose, and the manner how such an effect may be brought about. By placing before us a physical modus operandi, it presents us with one conceivable form, by which such a state of things may result, which metaphisical considerations teach us does really obtain. I would therefore state, in further explanation, that I was desirous that the conclusions which I have drawn, especially those which render some long-cherished distinctions futile, should be deduced rather from the first principles of a physical theory, than from my own more metaphysical propositions, although in the present imperfect state of the former, the conclusions derived from the latter possess a higher authority; still, I thought it exceedingly desirable, to draw closer together, and to connect, if possible, though it should only be by a link of probable truth, the investigations of physics and metaphysics. Allow me to add, that though opinions adopted in earlier life, have, on this occasion, revived with augmented force, I have felt more disposed to affix them as consequences to another man's principles, than to advance them on my own unsheltered responsibility. I fear, however, that Mr. Exley will not feel flatter by this putative paternity, and that the new views of things, which his principles, when carried out, disclose to us, are not exactly those foreseen or contemplated by him.

I am, Sir, yours, &c.
BENJ. CHEVERTON.

A NEW QUESTION. BY O. C. F.

It is well known, that if a person buy 120 eggs at 2 for a penny, and 120 more at 3 for a penny, and sell the whole

at 5 for twopence, he will lose fourpencé by the transaction. Now, supposing he had bought 120 at for a penny, how many must he buy at 3 for a penny, so that, selling the whole at 5 for twopence, he may neither gain nor lose? And, again, supposing 120 bought at 2 for a penny in each case, how many must be bought at 3 for a penny, so that on selling the whole at 5 for twopence, there may be gained 10 per cent., 15 per cent.. and 19 per cent., respectively? And, lastly, is it possible, having bought 120 at 2 for a penny, to buy any number at 3 for a penny, to sell the whole at 5 for twopence, and gain twenty per cent.? If it is not possible, what is the reason?

This simple question is proposed in order to illustrate the nature and cause of a limit which sometimes occurs and excites surprise in inquiries relating to per centage gains.

MR.

MACKINTOSH'S FIFTH LECTURE ON THE ELECTRICAL THEORY OF THE UNIVERSE.

Mr. Mackintosh remarked, that men had divided the physical sciences into several branches for the convenience of study; but if we desired to obtain a complete view of the subject, we must put all the parts toge ther, and view nature as a whole: in this sense, we should find that geology and astronomy were intimately connected, and that the study of the one would reflect light upon the other. In connexion with the electrical theory, there were two points to be esdtablishe-first, that the earth was contracting into solid rock; second, that solid matter in large masses has been deposited upon the surface. With respect to the first point nothing more was required than to state the fact that the hardest rocks contained remains of animals and plants, which once lived and died, and were deposited upon the surface of the earth, but their remains were now found hundreds of feet beneath the surface. It thus appeared, that the surface of the earth was raised in many places hundreds, and even thousands of feet above the original surface; and this fact, alone, was sufficient to convince us of the deposition of matter upon the earth; but if any further proof were wanted, we may find it in the additional fact, that the stratified rocks were found in positions into which it is impossible they could have been thrown by a force acting from beneath, they must have been deposited in a solid state upon the surface.

The details of the geological arguments connected with the electrical theory of the universe will be found in No. 655 of the Mechanics' Magazine, which renders a more lengthy report of this lecture unnecessary.

NOTES AND NOTICES.

Stage-Couches were first introduced into Scotland in 1678. On the 6th of August, in that year, the magistrates of Glasgow contracted with William Hume, of Edinburgh, that he should run a coach between Edinburgh and Glasgow, - forty-two miles. Hume engaged with all diligence to run a coach with six able horses, that should "leave Edinburgh every Monday morning, and return (God willing) every Saturday night!"

French Steamers.-A grand French enterprise of steamers in the Mediterranean is nearly completed. Ten of them, each 500 tons, and magnificently fitted up on English models, are in the port of Marseilles, ready to commence the service. There are to be two lines, one from Marseilles to Constantinople, the other from Athens to Alexandria. They will intersect each other at the little island of Syra, and exchange passengers and dispatches. Between Marseilles and Constantinople they will touch at Leghorn, Civita Vecchia, Naples, Mes sina, Malta, Syra, and Smyrna. The departure will be so managed that three times per month three steamers, one coming from Marseilles, the second from Constantinople and Smyrna, and the third from Alexandria, will arrive at the central station at Syra; so that a person at Marseilles can receive on the 29th day an answer to a letter written to Constantinople or Alexandria; while at present forty-five or fifty days are employed in going and retuning between Marseilles and either of those places.-Sunday Times.

Paddle- Wheel Experiment.-A recent experiment has proved that the supply of water to the paddle-wheels of steam-vessels does not come from the surface of the water, or from the sides of the space through which the wheel moves at each evolution of the water, but from beneath. It was proved as follows:-A steam-vessel was moored at deep water, which was strewed (it being calm wea◄ ther,) with sawdust; the engine was then put in motion, and it was observed that the sawdust all around and every where, except immediately behind the paddle-wheels, remained undisturbed.-Times.

Transferring Plants.-An interesting improve, ment in the mode of transferring plants which thrive best in a humid atmosphere has recently been communicated to the Society of Arts. They are inerely planted in a box filled with moist earth, and covered with a glazed frame, rendered as airtight as possible. Captain Mallard, R.N., filled several cases with ferns and flowering plants at Sidney, some of which had not previously been introduced into England. The thermometer, when. the plants and flowers were placed in the case at Sidney, stood at 90 and 100. In rounding Cape Horn, about two months after, the thermometer was observed as low as 20, at 8 p.m., and the decks were a foot-deep in snow. A fortnight after, they were in the harbour of Rio Janeiro. In crossing the Line, the thermometer rose to 120, and on the arrival of the ship in the British Channel the ther-, mometer was as low as 50. The plants were not watered, and received no protection either by day or night, and yet were found in the most flourishing condition after eight months' confinement.

Rock-Blasting by Lightning.-Perhaps human ingenuity and daring were never more strongly

manifested than in a recent instance in Prussia. In order to get rid of a large rock, the expense of removing which, by ordinary means, would have been enormous, a deep hole was bored in it, into which was fixed a bar of iron, 28 feet high, for the purpose of attracting lightning. The experiment was successful. On the first thunder-storm, the rock was shattered into fragments, which, of course, were easily carried away.

Colossal Status of Shakspeare. Dr. Carpue lately at the Western Literary Institution, Leices ter-square, stated to the audience that he had an important communication to make on the subject of a statue to Shakspeare, the largest statue ever erected to an individual. The King had consented to be the patron, and the Queen the patroness of this plan. The statue to be raised on an elevation 200 feet above the level of the Thames. Tue pedes. tal to be 60 feet, and the statue 80 feet high. It was also projected that there should be a staircase by which the curious might ascend to the crown of Shakspeare's head; that there should be built near the statue a house, a fac-simile of that in which it is assumed Shakspeare was born, for the resi tence of the person who should be engaged to show the statue; and that such residence should be allotted to a female descendant of a sister of Shakspeare now alive, but who is in very humble circumstances, and who should also derive any benetit that might accrue from showing the statue. He further mentioned, that the expense would be 20,000., to be raised by subscription; but that no one was to subscribe more than one guinea. For such an object, and that was to be so pro luctive of immediate benefit, he doubted not that there would soon be an adequate amount of subscriptions. The communication, after surprise had somewhat subsided, was greeted with very enthusiastic applause. The Doctor did not say how the descendant of the Shakspeare family was in the interim to be taken care of, nor did he mention when the projectors and calculators expected that his colossal statue might be completed. Morning Herald.

Improved Thatching -The Somersetshire mode of thatching is preferable to all others. It consists in using unbruised straw, provincially called reed, instead of braised straw with the ears on it. The practice of Devon, Dorset, and Somerset, in this respect, is an example to all England, which we are surprised has not been more generally followed, as it lasts nearly a long again as common straw, and does not offer the temptation arising from grains of imperfectly thrashed corn, which induce mice and birds to infest the dwelling and make holes in the thatch. The mode of preparing the straw is simply to take a sheaf of wheat and to place it in a reed-press, made of two pieces of timber ten feet long, put on a stool, and having women to lay hold of the ears of corn, who draw out the straw and cut off the caps, and then bind up the sheaf for use. In this process women are usefully employed in wet weather, and the corn is much more easily thrashed when in short ears than when encumbered with the straw. The thatching work done with the reed will last ten years longer than that done with the common straw, and as to the appearance there is no, comparison; one is an elegant neat covering, and the other a slovenly ragged one. Many gentlemen possessing fancy cottages and rural habitations have been so struck with the neat and picturesque app arance of the cottages in the three Western counties, as to have sent for persons to prepare reed for them in the counties where their dwellings are situate.-Farmer's Magazine.

Another "First" Inventor of Steam Boats in America.-A writer in the Philadelphia United States Gazette claims for Rumsey, of Virginia, the honour of first propelling boats by steain in this country. It was many years before Fulton, and

Rumsey was considered a wild enthuriast. With the assistance, however, of a drunken blacksmith at Shepherdstown, hé constructed a boat which went up the Potomac against the current at the rate of half a mile the hour. The Legislature of Virginia granted him soine privileges, it is said, which his poverty prevented him from embracing. He afterwards went to England, where he was pa tronised, but died suddenly, leaving his family in indigence the usual melancholy fate of those who have enriched the world with their genius. But as to the matter of priority in the great invention alluded to, we believe it is pretty well ascertained that the first experiment in this country which had any thing like the merit of success, was by Fitch, on the Delaware river. The periodicals of the time contain a sketch of the boat, and an account of the experiment. Lieutenant Slidell, however, in his excellent work on Spain, found, in the Archives of Barcelona, authentic evidence that experiments in steam-navigation were successfully attempted in that harbour several centuries since. To the indolent and voluptuous Spaniard, therefore, and neither to learned and enlightened England or France, we are indebted for the first conceptions of this immortal invention. (!)-New York Evening Star.

Beetroot Sugar.-A refinery of sugar from the beet-root is being erected at Thames Bank, Chel. sea, which it is expected will be in operation in about six weeks. In the vicinity of the metropolis, during the past summer, a great many acres of land have been put into cultivation with the rootat Wandsworth and other places. The machinery will be principally on the plans of the vacuum pans, and a pure refined sugar will be produced from the juice by the first process of evaporation, after it bas simply undergone the process of discolorisation. Another part of the premises is appropriated to the manufactory of coarse brown paper from the refuse, in which it is extensively used in France. In case the government do not interfere, and, by rendering the product exciseable, retard or prohibit its mn. nufacture, several individuals have it in contempla. tion to establish refineries in different parts of the kingdom for purifying sugar, which may be produced in agricultural districts for domestic or individual use. A retinery has lately been established at Belfast, in the vicinity of which town upwards of 200 acres of land have been put in cultivation with the beet root for the manufacture of sugar.

The publication of the Supplement to Vol. XXV. is unavoidably postponed until the 1st of December.

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