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Indeed, this purified ether appeared by every trial to be purer than I ever faw it, even when made after the beft ufual method, and in the most careful manner. The only inconvenience attending this procefs is, that a vaft quantity of ether is loft. Not above three or four ounces of a pound of common ether remain after the purification. As the greatest part of the ether is certainly mixed with the water that is used in the procefs, it may, perhaps, be worth while to put that water into a retort, and to distil the ether from it, which must come fufficiently pure for common ufe.

It is commonly believed, that water combines with the pureft part of ether, when those two fluids are kept together; whereas, by the above defcribed procefs, the contrary is eftablished: perhaps when ether is kept in contact with water for a long time, the pureft part of it may appear to be loft, because the ether may be combined with, and may retain fome water in itself, at the fame time that the water combines with and retains fome ether; whereas the cafe may be different when the ether is quickly washed in water, and is immediately after feparated from it: but in refpect to this I have yet not made any experiments, fo as to be able to decide the

matter.

EXPERIMENTS RELATING TO THE

EXPANSION OF MERCURY.

THE difficulty and uncertainty attending the various methods hitherto propofed for inveftigating the expanfion of quickfilver, or it's increafe of bulk when rarified by a given degree of heat, determined me to contrive fome method by which this purpofe might be effected with more certainty and precifion. After various experiments, I hit upon the following me. thod, which to me seems both new and capable of great accuracy, though in this I may be deceived.

Firft, having blown.a ball to a ca pillary tube, fuch as are commonly afed for thermometers, I weighed it,

and found that this empty thermome ter was equal to 79,25 grains. This empty glafs, previous to it's being weighed, was rendered as perfectly clean as poffible, which is a neceffary precaution in this experiment, which depends upon a very great accuracy of weight. Then I introduced fome mercury into the ftem of this thermometer, taking care that none of it entered the ball, and by adapting a scale of inches to the tube, obferved that 4,3 inches length of the tube was filled with the mercury. The thermometer was now weighed again, and from this weight, the weight of the glafs found before being fubtracted, the remainder, viz. 0,24 grains fhewed the weight of fo much quickfilver as filled 4,3 inches of the tube. Now the ball of the thermometer, and also part of the tube, were entirely filled with quickfilver: then, in order to find out the weight of the mercury contained in it, the thermometer was weighed for the last time, and from this weight the weight of the glafs being fubtracted, the remainder, viz. 3205 grains, fhewed the weight of the whole quantity of quickfilver contained in the thermometer.

By comparison with a graduated thermometer in hot and cold water, I made a fcale to the new thermometer according to Fahrenheit's, and by applying a fcale of inches found that the length of 20 degrees in this fcale was equal to 1,33 inches. But 0,24 grains was the weight of fo much mercury as filled 4,3 inches length of the tube; therefore, by the rule of proportion, it will be found, that the weight of fo much quickfilver as fills 1,33 inches of the tube, viz. the length of 20 degrees, is equal to 0,0742 grains nearly, and that the weight of fo much quick filver as fills the length of the tube that is equivalent to one degree, is equal to 0,00371 grains. Now it is clear, that the weight of the whole quantity of quickfilver contained in the thermometer is to the weight of fo much quickfilver as fills the length of one degree in the tube, as the bulk of the whole quantity of quicksilver

II

quickfilver in a given degree of heat, to the increase of bulk that the fame whole quantity of quick filver acquires when heated of but 1 degree; viz. 32,05 grains is to 0,00371 grains, as I is to 0,0011+; fo that, by this experiment, it appears that 1 degree of Fahrenheit's thermometer increafes the bulk of mercury not above Tooths parts. In this procefs, a fmall deviation from mathematical exactness is occafioned by the fmall difference of weight between the quickfilver of the tube when firft weighed and when it is afterwards heated to 1 degree; but by an eafy calculation it will be found, that this difference is fo exceedingly fmall as not to be perceived by our exacteft weighing and measuring inftruments. For clearnefs fake, Ifhall fubjoin the calculation of the above related experiments, difencumbered from words. Here the decimals are not computed to a very large number, that being unneceffary for this purpose.

increases the bulk of a quantity of
quickfilver ofths parts, viz.
if the bulk of a quantity of quickfil-
ver in the temperature of 50 degrees
is equal to 100,000 cubic inches, the
bulk of the fame quantity of quick-
filver in the temperature of 51 degrees
will be equal to 100,009 cubic inches.

It is almoft fuperfluous to mention,
that the cavity of the tubes employed
for thefe experiments must be perfect-
ly uniform throughout. The scales
to be used for this method fhould be
fo exact as to be turned by the hun-
dredth part of a grain when charged
with about half an ounce weight.

From thefe obfervations the method of graduating, or of determining the length of a degree in a new thermometer, is eafily deduced, the only requifites for the calculation being the weight of a quantity of quickfilver, which fills a known length of the tube, and the weight of the whole quantity of quickfilver contained in the thermometer when filled. Suppose, for instance, that, in making a new thermometer, it be found that the weight of fo much quickfilver as fills five inches length of the tube is equal to ten 0,24 grains. grains, and that the weight of the whole quantity of quick filver contained in the thermometer weighs 300

Weight of the glafs, 79,25 grains.
Weight of fo much
quick filver as fill-
ed 4,3 inch.length
of the tube,
Weight of the whole
quantity of quick-

filver contained in 32,05 grains. grains; it is plain that if the whole

the thermometer,

Length of the tube equal to zo de

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1,33 inches.

0,0742=

I : 0,00371 32,05 0,00371 :: 1: 0,00011 +to the expanfion occafioned by one degree of heat.

Having repeated this experiment with other thermometers, and by fimilar calculations, each procefs gave arefult little different from the others, which irregularity is certainly owing to the imperfection of my fcales, which are not of the niceft fort: but taking a mean of various experiments, it appears that I degree of heat, according to Fahrenheit's thermometer,

quantity of quickfilver weighs 300
grains, Tooths parts of it will weigh
0,027 grains. But the weight of fo
much mercury as fills five inches of
the tube is equal to 10 grains; there-
fore, 0,027 grains weight of quickfil-
ver must fill 0,0133 inches of the tube,
and this is equal to the length of 1 de-
gree, or the double, treble, &c. of it is
equal to two, three, &c. degrees.

By this means the fcale may be
made, that is, it may be divided into
degrees; but the numbers cannot be
added to them without finding which
of thofe degrees correfponds with the
freezing point or boiling point. Either
the point of boiling or freezing may
be found by experiment, or any other
point may be afcertained by compari-
fon with another thermometer, and
then the other degrees are nominated
accordingly.

DESCRIPTION

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DESCRIPTION OF A THERMOME

TRICAL BAROMETER.

THE determination of the various degrees of heat fhewn by boiling water under different preffures of the atmofphere, has been attempted by va. rious perfons, but it was lately compleated by the accurate and numerous experiments of Sir George Shuckburgh, member of this Society. His valuable paper is inferted in the LXIXth vol. of the Phil. Tranf. Upon confidering this paper, I thought it poffible to conftruct a thermometer with proper apparatus, which, by means of boiling water, might indicate the various gravity of the atmofphere, viz. the height of the barometer. This thermometer, together with the fuitable apparatus, might, I thought, be packed into a small and very portable box, and I even flattered myself, that with fuch an inftrument the heights of mountains, &c. might perhaps be determined with greater facility than with the common portable barometer. My ex

particular degrees of heat which are fet down in Sir George Shuckburgh's table. With this inftrument the barometrical height is fhewn within onetenth of an inch. The degrees of this thermometer are fomewhat longer than one-ninth of an inch, and confequently may be fub-divided into many parts, especially if a nonius is ufed. But the greatest imperfection. of this inftrument arifes from the fmallness of the tin-veffel, which does not admit a fufficient quantity of water: and I find, that when a thermometer is kept in a fmall quantity of boiling water, the quickfilver in it's ftem does not stand very steady, fometimes rifing or falling even half a degree; but when the quantity of water is fufficiently large, for inftance is ten or twelve ounces, and is kept boiling in a proper veffel, it's degree of heat under the fame preffure of the atmofphere is very fettled.

THE HERMITAGE.

A TALE.

F all the misfortunes incident to

pectations are far from having been human nature, not one, perhaps, difappointed; and although the inO ftrument which I have hitherto conftructed has various defects, I have, however, thought of fome expedients which will undoubtedly render it much more perfect: I shall then prefent to this Society a more particular account of it, and also of the experiments which I intend to make with it. The inftrument in it's prefent ftate confifts of a cylindrical tin veffel, about two inches in diameter and five inches high, in which veffel the water is contained, which may be made to boil by the flame of a large waxcandle. The thermometer is faftened to the tin veffel in fuch a manner as that it's bulb may be about one inch above the bottom. The fcale of this thermometer, which is of brafs, exhibits on one fide of the glafs tube a few degrees of Fahrenheit's scale, viz. from 200 degrees to 216 degrees. On the other fide of the tube are marked the various barometrical heights, at which the boiling water fhews thofe

can be found fo myfterious in it's rife and progrefs, and fo ferious in it's confequences, as that which is ufually called being croffed in love. It not only attacks the heart in it's moft refined feelings, but extends it's gloomy influence to the intellects, in fo ftrong a degree as to occafion a temporary phrenzy, nearly bordering on infanity, and which, if not checked and foothed by the timely aid of reafon, is too apt to end in that most deplorable of calamities. Those who never felt the strong, the impetuous, and (I will call them) the exquifite anxieties which are infeparable from that tender paffion, and conftitute it's very effence, will treat this fentiment as the mere chimera of Fancy, and the airy child of Delufion: fuch perfons will class the hero of the following tale with romantic madmen, nor will the writer of it be exempt from his fhare of the mistaken ridicule; but the gentle sympathy of

candid

candid minds will more than indemnify him for the imputation of folly,

and vindicate thofe emotions which have been too forcibly realized in truly fentimental breafts.

Baron Hargrove was defcended from an ancient family of that name and title in the county of Norfolk; and it was his fate to live in an age when ignorance, and, ftill more, fuperftition, left very little fcope for the exertion of genius, or even for the free use of reafon. He was, however, endowed with every accomplishment which nature could bestow; and these were improved by the early exertions of an afpiring mind and vigorous conftitution. He excelled every rival in the manly feats of chivalry, was ever moft diftinguished in the labours of the chace, (for fo they might then well be called;) and, though not yet in his nineteenth year, his youthful brow was adorned with martial laurels, which made him at once the envy and admiration of the most experienced captains and warriors. He was proceeding with eager ftrides in this arduous career of toils and perils, when Love, that lord of reafon, and tyrant of the heart, gave a fudden turn to his purfuits, and difcovered an object ftill more attractive than that of fame, to be the very foul and centre of his ambition.

It was no fmall triumph for the fair daughter of Earl Charlemont to captivate a man who was fighed for in fecret by almost every lady who had beheld him; and she was, perhaps, the only one of her capricious fex who would for a moment have proved infenfible to his love. With all that timid refpect and veneration which is the affured teft of fincerity, he breathed out his tender regards to the dear object of his affection: the most coftly prefents were added to the gentle voice of perfuafion; and nothing was neglected which could poffibly tend to prove the ardour of his own paffion, or awaken that genial fpark which he fondly hoped might lie dormant in the bofom of his mistress.

Finding himself deceived in this pleafing expectation, and being one

day difmiffed with a referve which difappointment mifconftrued into dif dain, he took a hafty refolution to hide thofe forrows in a defart, which the malicious eye of infulting pity might only render more infupportable, fhould he continue to mix in the fashionable circles. Had he lived in our wife days of heroic refinement, he would doubtlefs have ended the tragedy with more eclat; that is, he would have died like a gentleman; either by the fword, or (fince unfortunately piftols were not then invented) by the more inglorious aid of a cord; especially as the final date of his unfuccessful courthip happened to be in November: but his mind not being fufficiently enlightened by philofophy to know that fuicide was not a crime,it purfued fuggeftions of a lefs violent tendency, and Solitude became the only witness of it's penfive effufions. The place of his retreat, though not far removed from his paternal inheritance, was fo judiciously chofen, and well calculated for the purposes of concealment, that had not mere accident driven him from it, he might have eafily indulged the refolution he had formed of remaining there till death fhould release him from his folitary mifery.

Affliction is faid to be the parent of Devotion; and it is well known to what feats of extravagance that may lead the most rational beings, when cherifhed to excefs, and unrestrained by the power of reason. In lefs than a week after his retirement, the gay and amorous young baron had undergone the most effectual metamorphofe in drefs as well as difpofition: his fhoes were cut into the form of fandals, his hat was twifted into that of a cowl, bull-rushes plaited together formed a tolerable girdle, and a tough hazel twig effectually fupplied the want of difcipline. In a word, his food, his drink, and every thing about him, did not lefs agree with the life of a her. mit, than the gloominefs of his abode, which was fituated at the foot ofarock; andhe who a few days before was fighing out his foul at the feet of a miftrefs, and who confidered her fmiles or

.

frowns

frowns as the criterions of his fate, was now employed in repeating the moft earnest vows of eternal and inviolable chastity.

Eleonora, who in reality was far from being, as he supposed, infenfible to his love, and who had only practifed the arts of her sex with the ufual views of prolonging her triumph and enhancing the price of her charms, was now not lefs mortified than furprized at his fudden difappearance: though she had feemingly admitted a rival with marks of encouragement, Hargrove had in every refpect the preference in her heart; and to him her hand would doubtless have been yield ed, had he waited with patience for the happy moment of compliance. However, after a few weeks of fufpenfe and regret, Eleonora, finding that he did not return, acted her part with much feeming indifference and refolution, and even went fo far as to marry a perfon who fhe knew had very few pretenfions to his merit and vir

tues.

It was a common practice with thofe who were unfuccefsful in their facrifices to Hymen, to apply to fome holy father, by whofe interceffion they might obtain that bleffing from Heaven which can alone render conjugal felicity compleat. Eleonora was too impatient for maternal honours to fuffer many unfuccefsful months to efcape, without having recourfe to the ufual mode of redrefs. With this view she set out, in company with her husband, on a pious vifit to a reverend friar, who was celebrated for having relieved numbers on fimilar occafions. They had not proceeded many miles on their journey, which lay through bye-ways, and almost impenetrable thickets, when the dogs, who made part of the convoy, ftopped on a fudden before a wood, which rofe in a gradual afcent from the foot of a steep mountain, and by their eager emotions convinced the travellers that fome wild beaft was concealed behind the bushes. They therefore approached the place with caution; and having difcovered the fuppofed monster in his den, VOL. III.

(which was in reality no other than Hargrove in his cave) an arrow was directed to the spot where it lay concealed. The arrow had been fo well shot, as to glance on the bridge of his nofe, and the blood which flowed plentifully from the wound was no inconfiderable addition to the oddity and terror of his appearance. The pilgrims having with infinite difficulty made their way to his cell, were fo far from recollecting the features of their old friend, in his prefent condition, that they could hardly be fatisfied that he was a human being, and attributed his feeming anger to the pain occafioned by the wound he had received: they therefore began by apologizing for the involuntary injury, whilft he gazed on them alternately with looks of filent furprize and indignation. But when they proceeded to explain the nature and object of their journey, imagining they had by fome means been inform ed of his abode, and doubting not that they meant only to fport with his griefs, and infult his misfortunes, he flew into the most violent paroxifm of rage, expreffed in terms as well fuited to the temper of his mind as inconfiftent with the garb and character he had affumed. His gefture and actions, indeed, were fuch as threatened the moft defperate confequences to the new-married couple, who made a precipitate retreat; unable otherwise to account for fo rude a reception from the man of God, than by concluding him poffeffied by the spirit of the devil. Hargrove was obliged to quit his retirement in confequence of this unexpected vifit, and went in quest of another retreat in a different part of the kingdom; being obliged by the vows he had made to lead the life of a hermit for the remainder of his days. His religious fervor was, however, confiderably abated; and he refolved in his own mind to reserve a confiderable portion of his property for his own private ufe; and not, like fome of the brotherhood, to truft entirely to Providence for a precarious and miferable provifion, Purfuing his way to the north, he at last took up his abode in

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