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“But after his despair receives feelings could not be painted. In full confirmation from the heart fact, the airectiorate astonishment searching speech of Henry, his feel and pious horror of Henry were fitings are leared with horror, and his ter for deiineation, than the Glent, agony will give no sign. For the fullen, and uncommunicative de. moment of the picture is not when pair of Beaufort. Beaufort is said to be grinning with " The rage of delineating to the mortal anguish; but the more aw- eye all that is reckoned fine in writ. ful moment, when having heard the ing may be illustrated also, in the request of Henry, he finks, of conse- performances of and faquence, into the deepest defpon. mous artists. In Gray's Ode on the dency. Before that it would have Spring, we have the following alle., been no other than the picture of a gorical description : man, of any man whatever, expir. ing with bodily pain. If indeed Lo! where the rosy-bosom'd hours, the picture is to express any thing

Fair Venus' train, appear, peculiar or characteristic, it must be

Disclose the long expecting flowers, despair formerly excited, but now

And wake the purple year. ratified and confirmed by the speech

« The hours accordingly, adornof Henry.

ed with roses dispared as the poet

describes them, are reprefented on King. Lord Cardinal, if thou canvass, as a company of jolly dam

think'st on Heaven's bliss, sels, twitching or pulling another Hold up thy hand, make signal of very beautiful and buxom female, thy hope.

who is represented as sleeping on a He dies, and makes no fign:-0 bank, and clothed with a purple God, forgive him!

petticoat. Seeing such things, it is

• impoffible not to think of Quarles's « In short, the passage, highly or Hugo's Emblems. The thought, sublime and affecting, as it must who Thall deliver me from this be acknowledged, is more poetical body of fin and death?” is present. than picturesque : and the artist hased to the eye, in one of them, by wasted, on an ill-chosen subject, his the figure of a man enclosed within powers, rather of execution in this the ribs of a monstrous and hideous instance, than of invention. Surely skeleton. In truth, the inventor of we see no masterly invention in the the prints in some editions of the pretervatural being placed behind Pilgrim's Progress (where, among or beside the cardinal; for though others, Christian is represented as the poet has said, in the character of trudging along like a pedlar, with a Henry, that a 'busy meddling fiend burden on his back) is entitled to • was laying liege to his soul;' yet the merit of priority in the extravaås the speaker did not actually see gance of such inventions; for let it the fiend, there was no occafion for be remembered, that it is only a. introducing biin, like the devil in a gainft extravagancies and misappli. puppet-Mow, by the Gide of his bed, cations, and not against the invenNor is there much invention in the tion itself, that I have ventured to stale artifice of concealing the coun- remonftrate." tenance of the king, because his



OBSERVATIONs on the Means of confining Heat, and directing ics




«THAT heat passes more freely will grow so hot as to render it im

1 through some bodies than possible to hold it in the hand withthrough others, is a fact well known; out being burnt; but the wood may but the cause of this difference in be held any length of time in the the conducting powers of bodies, fame situation without the least in. with respect to heat, has not yet convenience; and even after it has been discovered.

taken fire, it may be held till it is “ The utility of giving a wooden almost entirely cousumed; for the handle to a tea-pot or coffee-pot of uningtained wood will not grow hot, metal, or of covering its metallic and, till the flame actually comes in handle with leather, or with wood, contact with the fingers, they will is wellknown: but the difference in not be burnt. Jf a finall slip or the conducting powers of various tube of glass be held in the flame of bodies with regard to heat, may be the candle in the same manner, the Thewn by a great number of very end of the glass by which it is heid fimple experiments ;- such as are will be found to be more heated in the power of every one to make than the wond, but incomparably at all times and in all places, and less so than the pin or nail of metal; almost without either trouble or ex. :--and among all the various bodies pence.

that can be tried in this manner, no “If an iron nail and a pin of two of them will be found to give wood, of the same form and di- a passage to beat through their submensions, be held successively in the stances with exa&rly the same degree flame of a candle, the difference in of facility. the conducting powers of the metal “To confine heat is nothing and of wood will manifest itself in a more than to prevent its escape out manner in which there will be no of the hot body in which it exists, room left for doubt. As soon as the and in which it is required to be re, end of the pail, which is exposed tained; and this can only be done in the flame of the candle, begins by surrounding the hot body by 10 be treated, the other end of it some covering composed of a sub

{tanco Stance through which heat cannot Juding powers depend essentially pals, or through which it passes with upon the extreme mobility of their great difficulty. If a covering could parts; in thort, that they rather be found perfectly impervious to transport heat than allow it a par. heat, there is reason to believe that fage. But I will not anticipate a a hot body, completely surrounded subject which I propose to treat by it, would remain hot for ever; more fully at some future period. but we are acquainted with no “ The conducting power of any such substance; nor is it probable solid body in one solid mass, is much that any such exifts.

greater than that of the fame body “ Those bodies in which heat reduced to a powder, or divided passes freely or rapidly, are called into many smaller pieces: an irou conductors of heat; those in which it bar, or an iron plate, for instance, makes its way with great difficulty, is a much better conductor of heat or very slowly, non-conductors, or bad than iron filings; and faw-duft is a conductors of heat. The epithets, better non-conductor than wood. good, bad, indifferent, excellent, &c. Dry wood-aflies is a better nonare applied indifferently to conductors conductor than either; and very and to non-conductors. A good con- dry charcoal reduced to a fine ductor, for instance, is one in which powder is one of the best non.cona heat paffes very freely; a good non- ductors known; and as charcoal is. conductor is one in which it passes perfectly incombustible when con. with great difficulty; and an indif- fined in a space where fresh air can ferent conductor way likewise be have no access, it is admirably well called, without any impropriety, an calculated for forming a barrier for indiffereut non-conductor.

confining heat, where the heat to be " Those bojies which are the confined is intense. worst conduétors, or rather the best “But among all the various sub. lion-conductors of heat, are beft ad stances of which coverings may be apted for forming coverings for con. formed for confining heat, none can fining heat.

be employed with greater advan. “All the metals are remarkably tage than common atmospheric air. good conductors of heat:--wood, It is what nature employs for than and in general all light, dry, and purpose; and we cannot do better Spungy bodies, are non-conductors: than to imitate her. giaís, though a very hard and com- “ The warınch of the wool and pact body, is a non-conductor. Merfur of beasts, and of the feathers of cury, water, and liquids of all kinds, birds, is undoubtedly owing to the are conductors; but air, and in ge- air in their interstices; which air, neral all elastic Auids, steam not being strongly attracted by these even excepted, are non conductors. substances, is confined, and form's a

“Some experiments which I have barrier which not only prevents the lately made, and which have not yet cold winds from approaching tbe been published, have induced me to body of the animal, but which opsuspect, that water, mercury, and poses an almost insurmountable ob. all orber non-elastic fuids, do not stacle to the escape of the heat of permit heat to pass through them the animal into the atmosphere. from particle to particle, as it un. And in the same manner the air in doubtedly passes through folid bo- snow serves to preserve the heat of dies, but that their apparent con. the earth in winter. The warmth

of all kinds of artificial clothing it is the confined air fhut up bes: may be thewn tv depend on the tween the two windows, and not fame cause; and were this circum- the double giaís plates, tha: renders stance more generally known, and the pallage of heat through them so more attended to, very important difficult. Bere it owing to the inimprovements in the management created thickness of the glass, a filof heat could not fail to refult from gle pane of glass twice as thick it. A great part of our lives is would answer the saine purpose spent in guarding ourselves against but the increated thickness of the the extremes of heat and of cold, glass of which a window is formed, and in operations in which the use is pot found to have any sensible of fire is indispensable; and yet how effcét in rendering a room warmer. little progrets has been made in that “ But air is not only a non-coa. nofi utelul and most important 3ictor of heat, but its uon-conduct. of the arts, the management of ing power may be greatly increased. heat!

To be able to form a just idea of the “ Double windows lave been in manner in which air may be renderuse many years in most of the north- ed a worse conductor of heai, or, ern parts of Europe, and their great which is the same thing, a better utility, in rendering the houses fur- non-conductor of it, than it is in its nished with them warm and com- natural unconfined state, it will be fortable in winter, is universally ac-' necessary to consider the manner in knowledgedi,----but I have never which heat passes through air. Now heard that atiy body has thought of it appears, from the result of a num. emploving them io hot countries to ber of experiments which I made keep their apartuients cool in fun, with a view to tie invitigat on of mer; yet bow easy and natural this subject, and which are publih. is this application of fo finple and ed in a paper read before the Royal useful an invention! If a double Society, that thougia the particios of window can prevent the heat which air, each particle for itself, can re. is in a room from pailing out of it, ceive heat from other bodies, or one would imagine it could require communicate it to them, yet there no great effort of genius to discover is no communication of brat bethat it would be equally efficacions tween one particle of air and ano. for preventing the heat without ther particle of air. And from from coming io. But natural as hence it follows, that though air this conclufion may appear, I be. may, and certainly does, carry off lieve it has never yet occurred to heat, and trauíport it from one any body; at least, I am quite cer- place, or from one body to another, tain that I have never seen a double yet a mass of air in a quiescent window either in Italy, or in any state, or with all its particles at reft, other hot country I have had occa- could it remain in this fate, don to visit

would be totally impervious to heat; " But the utility of double win or such a mass of air would be a dows and double walls, in hot as perfect non-conductor. well as in cold countries, is a matter “Now if heat patres in a mass of of so much importance, that I shall air merely in confequence of the Lake occasion to treat it more fully motion it occafions in that air,-if in another place. In the mean it is transported, not suffered to time, I Mall only observe bere, that pass, in that case, it is clear that


whatever can obftruet and impede ver, though it is not probable that the internal motion of the air, must there is any esential difference in tend to diminish its conducting pow. the chymical properties of those two. er: and this I have found to be the kinds of hair. care in fact. I found ihat a certain ~ But it is not only the fineness quantity of heat which was able to of the parts of a substance, and its make its way through a wall, or ra- being a non-conductor, which renther a sheet of confined air an der ic proper to be employed in the inch thick in 9 minutes, required formation of covering to confine 20 minutes to make its way through heat; there is still another prothe same wall, when the internial perty, more occult, which seems to motion of this air was impeded by have great infinence in rendering mixing with it part of its bulk of some substances better fitted for this cider-down, of very fiue fur, or of use than others; and this is a cerfine filk, as fpun by the worm. tain attraction which subGifts be.

* But in mixing bodies with air, tweea certain bodies and air. The in order to impede its internal mo. obstinacy with which air adheres to tion, and render it more fit for con- the fine fur of beasts and to the fining heat, such bodies only must feathers of birds, is well known; be chosen as are themselves non. and it may easily be proved that conductors of heat, otherwise they this attraction must affist very pow. will do more harm than good, as I erfully in preventing the motion of have found by experience. When, the air concealed in the interstices of initead of making use of eider- those substances, and consequently dowo), fur, or fine Glk, for imped. in impeding the passage of heat. ing the internal motion of the con- through them. fioed air, I used an equal volume of " Perbaps there may be another exceedingly fine filver-wire Alatied stiil more bidden cause which ren. . (being the ravellings of gold or fil ders one. substance better than anver lace), the passage of the heat other for confining heat. I have through the barrier, so far from be- sewn by a direct and unexceptioning impeded, was remarkably facili. able experiment, that heat can pass tated by this addition; the heat pair- through the Torricellian vacuum, ing through this compound of air though with rather more difficulty and fine threads of metal much than in air (ihe conducting power suoner than it would have made its of air being to that of a Torricellian way through the air alone.

vacuum as 1000 to 601, or as 10 to • " Another circumstance to be at 6, very nearly); but if heat can tended to in the choice of a fub pass u here there is no air, it muft in stance to be mixed with air, in or- that case pass by a medium more der to form a covering or barrier for subtile than air ;--a medium wbich confining heat, is the foreness or most probably pervades all folid bosubtility of its parts; for the finer dies with the greatest facility, and they are, the greater will be their which must certainly pervade either furface in proportion to their soli. 'the glass or the mercury employed dity, and the more will they impede in making a Torricellian vacizum. the motions of the particles of the “Now, if there exists a inedium air. Coarse horse-hair would be more subtile than air, by which heat found to answer much worse for this may be conducted, is it not possible purpose than the fine fur of a bea• that there may exist a certain affi.

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