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On Warming School Rooms, &c.

As the season is fast approaching, in which fire will become a necessary article in domestic comfort, we insert the following observations, which we have had in our possession for some time.

TO THE EDITOR OF THE IMPERIAL MAGAZINE.

SIR, ON visiting a Sunday School, of two rooms, one over the other, I observed a stove in the lower one, which heated the upper, by a sheet-iron case round the stove and flue, open at the bottom, and shut at the top; with a valve in the side, for letting out the hot air, which was continually replaced by the

cold air admitted at the bottom, and heated on the principle of the patent hot air-stoves. This appeared an invention that may hereafter be extended, to deliver the chimney-sweeps from their worse than negro depravity. The economy in fuel also recommends it; and the little room it takes up, must be an advantage to houses and manufactories built suitably for it. No doubt, the heat let out in the upper room, was taken from the lower; but the object is to save the heat from waste by misapplication, which is invariably the case where there is too great a supply. How many houses are damp and comfortless, which at the same time consume as much fuel as makes the air over the chimneys abundantly warm. If a house of four or six stories, floors, or flats, have but one fire in the bottom, this invention may be applied to heat any or all of the rooms over it. The iron flue which takes up the smoke, may be cased in a small brick funnel, which holds the hot air, until it is let out by an aperture in each room. A small chain in the flue, passing over a roller at the top, and within reach at the bottom, will draw up and down a brush, or other proper instrument, to cleanse the flue. In manufactories, the stove may be cased with sheet iron, as mentioned. Two or three inches' interstice between the

case and the stove, and its flue, heats the air, and it may pass with safety through all the floors, either in the centre, or whatever position is most convenient. In chimneys already built on the old plan, the flue may be inserted as described; and the chim

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SIR,

On reading Sir Richard Phillips' reply to my strictures, inserted in your Magazine for August, p. 563, or rather to the advocates of the philosophy which in supreme contempt he denominates, "the legerdemain philosophy," it appeared to me at first unnecessary to make any further remarks on the subject; but judging that some of your numerous readers may expect a few observations on his paper, I present the following, for a place in the Imperial Magazine, if they meet your approbation.

THOS. EXLEY.

Bristol, Sept. 16, 1819. AMONG the fanciful agents which the Newtonian Philosophy is said to have introduced into nature, I cannot conceive the reason why the epithet ETERNAL, is connected with PROJECTILE FORCE; surely none can sanction the phrase "ETERNAL PROJECTILE FORCE," except those who impiously deny creation, and assert the eternity of matter: but is it not a curious fact, that Sir Richard himself admits of the projectile force? Even he cannot do without it; and hence he frequently speaks of the momenta of bodies in the direction of their motions; of forces generating, and destroying the momenta, | and deflecting moving bodies from the line of their direction, &c. Is it not strange for him to rail at Newton, for inventing this force, (though he never invented it,) and then freely employing the same "fanciful agent?" This force, however, is not an invention to serve a theory, it is not fanciful, but presents itself in every phænomenon of matter.

But the " special exposure" of five appeals made to credulity, claim our notice, of which the first respects the terms, Attraction and Gravitation; and here we observe, that if genuine philosophy may not " give names to allowed to give a name, or at least to effects," yet the philosopher may be adopt one, expressive of any thing he has occasion frequently to mention, or introduce in his discourse. Again, if we grant, "that it is the bounden duty of every legitimate philosopher, to adopt an explanation of the proximate cause of an effect," should he know the cause, we likewise insist, that if he cannot give the explanation, it is his duty to acknowledge his inability but surely, the Newtonians cannot be accused of "refusing to in

quire into the cause:" they, of all philosophers, are the most rational, and most diligent inquirers into the causes of phænomena; using the combined efforts of continued experiments and observations, to obtain from the lips of Nature herself, the secret springs which give rise to her beauty, and life to all her charms.

An attempt is made to prove, that the Newtonians, by the term attraction, necessarily mean a force, whatever they affirm to the contrary; for they invent a force to oppose it; if so, they have laboured in vain; to what purpose was the legerdemain employed to call up innate attraction, if they were obliged to exercise their hocuspocus, to conjure the same into a nonentity? The truth is, they every where see the projectile force, of bodies in motion, which is nothing else than their tendency to continue moving in the same line of direction, with the same velocity; or, in other words, to preserve their momenta in that direction. In the planets, it appears evidently, that the tendency to continue in the same direction is constantly destroyed, by some power deflecting them toward the sun, as if the sun had hold of them, and attracted them always from their course in a line drawn to his centre. Hence, they say, the sun attracts the planets, &c.; and surely, they may well be allowed the free use of the term attraction, to designate an effect, which appears very much like the act of drawing; especially when they distinctly inform us, they cannot tell what the cause or real operating force is, or where it reside

whether in matter or out of it, only that they can judge of its quantity and direction, and the law of its operation, by the effects produced on the bodies subject to its influence; and as the force and its effect reciprocally measure each other. Thus, by the word attraction of a body, is denoted very appropriately, the effect, or the measure of the force, whatever it is, and its direction toward the body, which, for conveniency, is said to attract the other; and the name is not "by themselves converted into a force or tendency," but very properly serves to express the effect, which measures the quantity of force or tendency, and at the same time readily conveys the idea of the direction of that force. Hence, it is no otherwise the name of a force, than as that force is expressed by its proper measure, that is, by its effects; in this way, it is indeed, necessarily expressive of force.

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these forces will vary, if the distance vary; and therefore, the planet may sometimes actually approach nearer to the sun, and at other times recede. The deflection is, in fact, an effect continually observed; and from this most evident fact, it is legitimately inferred, that the "planets have a tendency to fall to the sun;" the Newtonians, do not, therefore, at all deduce the conclusion from the fall of a stone! A quotation from Mr. Cotes' excellent preface to Newton's Principia, will properly close this part of my observations. "That every body perseveres in its state, either of rest, or of moving uniformly in a right line, unless in so far as it is compelled to change that state by forces impressed, is a law of nature universally received by all philosophers. But from thence it follows, that bodies which move in curve lines, and are, therefore, continually going off from the right lines that are tangents to their orbits, are by some continued force retained in those curvilinear paths. Since then the planets move in curvilinear orbits, there must be some force operating, by whose repeated actions they are perpetually made to deflect from the tangents."

But, Sir Richard admits the law of this force: very good; this law was Newton's great discovery, and the glory and crown of all his discoveries in astronomy. This great acquisition has vastly extended the field of science, and unfolded mysteries in nature not otherwise to be unravelled; and pre- The greatest part of the second" spesented beauties in the grand system cial exposure," is far beyond the reach of material existence, not otherwise of my capacity; and therefore, leaving to be seen. But we are told, that “ the sublime explanation of the eccenplanet does not face to the sun:" true; tricities of the planetary orbits, to perbut it falls towards the sun, and while sons of more skill in the mysteries of its tendency towards the sun would philosophy, I shall confine my obserhave carried it in a straight line, con- vations on this, and the fourth exnecting its place and that luminary, posure, to the application of geometry its momentum in the direction of its to astronomical science. And since motion, (its projectile force,) carries it geometry is conversant about quantiout of that line in advance; and it is ties, and their relations, any science, actually nearer the sun than it would as far as quantity is concerned, may have been if the attaction had not ex- be served by geometry: and since asisted, but farther from the sun than it tronomy, and physical science in gewould have been if the projectile force neral, every where contemplates quan(momentum in the direction of its mo- tities, as those of space, time, magnition) had not existed; that is, the tude of bodies, velocities, momenta, distance from the sun will be between with a variety of others, and the quanthe limits of the distances which would tities are frequently connected by nehave been attained by supposing first cessary relations, it will not be thought one tendency to exist alone, and then wonderful, if geometry should be abunthe other. But whether the planet dantly useful in physical astronomy; will be actually nearer to, or farther yet, they who make the application, from the sun, will depend on the pro- cannot be thought to be so void of portion of the two tendencies, and the sense, as to suppose that the physical angle contained by their directions; phænomena exist in virtue of the reand since the law of the tendency to-lations of the geometrical quantities. wards the sun is admitted to vary inversely as the square of the distance, it is allowed that the proportion of

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Newton is accused of a whimsical attempt to connect the motions of the moon, with the quantity expressed

by the versed sine of the first second of the quadrant!" and of making this versed sine" the measure of the equable power of nature, which carries the moon through the quadrant." Leaving those absurdities with the author of them, it may be observed, that as we estimate a cause by its effect, and since in a curve at any point, the deflection from the tangent, taken very near the point of contact, is truly measured by the versed sine of the very small arc of which it is the versed sine, it follows, that if a body move in the curve, its deflection from the tangent, which is the effect of the deflecting force, is truly measured, and consequently the deflecting force itself, whatever it is, is truly measured by the versed sine of the small arc described in a very small portion of time. Newton then, having calculated the versed sine, that is, having found the deflection of the moon, obtained a true measure of the force by which she is prevented from pursuing the line of her motion, and is continually brought into a new direction, so as to revolve about the earth; and by this means, he found that the force so measured, corresponded exactly with the general law of gravitation, and that a stone placed at the distance of the moon would fall just as much towards the earth, as the moon does in the same time; and consequently, he was authorized to consider the retention of the moon in her orbit, as a particular case of universal gravitation. The same may be otherwise demonstrated; the law of gravitation being admitted, (and Sir Richard himself admits the law,) for then the square of the periodical times will be proportional to the cubes of the distances; and hence, a body revolving round the earth at its surface, would complete its revolution in 84 minutes and 34 seconds, and the deflection from the tangent of this orbit, in one second, would be 161⁄2 feet, being precisely the space through which a stone, by common gravity, would fall in the same time.

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As to the third" especial exposure," too little is exposed; the objection ought to have been, that the whimsical theory offered to notice, not only does "not account for the phænomena of comets," but is incapable of explaining any phænomena in nature. This objection, as urged against the Newtonian physics, is utterly without No. 8. VOL. I.

foundation; but in respect to the visionary scheme before us, is perfectly just; for in this hypothesis every thing is darkly delivered, and no class of phænomena is exhibited with which the appearances pretended to be explained correspond; while we see in Newton's admirable theory, the most perfect harmony.

By whom" the fifth appeal to vulgar faith," has been exhibited as unanswerable," I cannot tell; but it will be sufficient "merely to observe," that the Newtonian theory rests on the sure basis of observations; and being once established, calculations may be founded on it; for though astronomical calculations are generally founded on observations, yet they may, in certain respects, be founded on theory, and often are so; and the calculations so conducted, agreeing with those entirely derived from observation, or rather agreeing with facts obtained by subsequent observations, not only as well, but more perfectly than the others, is a circumstance not unfriendly to the theory. But when some able mathematician shall have solved the great problem, proposed by Sir Richard Phillips at the close of his paper, we may expect to see more of the extraordinary qualities and advantages of this new philosophy, so called.

Question on the Catholic Claims. TO THE EDITOR OF THE IMPERIAL MAGAZINE.

SIR,-FEW have noticed with more regret than myself, the great silence that has prevailed in general over the kingdom, with respect to the " Catholic Claims." It is true, a few individuals have benefited society in publishing pamphlets, and distributing tracts, &c. expressive of the danger to which the Protestant Religion in this country would have been subject; yet these, comparatively speaking, will fall into few hands. I would therefore take the liberty, through the medium of your Miscellany, to propose to your readers the following question, to which I should feel much obliged if some one would favour me with an answer:

Would the union of the Protestant and Roman Catholic Religion, in the Imperial Parliament, tend to make the national compacts more secure, and more conducive to the welfare of civil ALPHA. and religious liberty?

Islington, August 7, 1819.
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North East View of Stromboli, distance about seven miles.

Short Account of Mount Stromboli, one of the Lipari Islands.

TO THE EDITOR OF THE IMPERIAL

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W. B.

Stalmin, Sept. 2, 1819. BEING on deck one evening, about ten o'clock, on the coast of Italy, the cliffs of Belvidere bearing S. E. by E. distant about three leagues, I was rather surprised to see Stromboli, the dis- | tance from which, according to an accurate chart, I found to be 50 miles: its fiery eruptions, which were plainly distinguishable, were continued with great frequency. Stromboli is the most northern of any of the Lipari islands, and bears nearly due N. from the promontory of Melazzo, distant about 60 miles; its shape is circular, from which circumstance, the Greek geographers called it Ergoyyon It consists of a single mountain, which at some distance bifurcates; one summit stretching to the N. E., the other to the S. W., the altitude about an English mile. The crater of this volcano, different from any other I have seen, is about one third from the summit, on its N. E. side, the edges of which project, and form a cliff. The ejected matter is sometimes thrown up

the distance of half a mile, and many ignited stones fall over the highest pinnacle of the volcano.

The eruptions from Stromboli are uninterrupted; they continue from age to age, only varying in degree; and how to account for this wonderful receptacle of igneous matter, many have been puzzled. Spalanzani asserts, that it consists of porphyry rocks, and that these rocks furnish matter for the present eruptions.

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We are entirely ignorant as to the date when this volcano began its activity; it is an epoch beyond any history. But we have accounts of its conflagrations, as transmitted by historians, prior to the Christian era nearly 300 years. There is not the least doubt, that it is of volcanic origin; and this seems to derive confirmation, from the appearance of a small rock, about two miles distant from its eastern side, of which no mention is made by historians; of this, the reason most probably is, that it has been thrown up by subterranean fire subsequent to the times in which they wrote. On its southern side, this island is thinly inhabited, the number is said to be about 1000 souls; I think its diameter cannot much exceed two or three miles.

According to the ancient mythology, this island was the seat of the god Eolus, who presided over the winds. See Virg. En. and Homer's Odyssey.

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