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family of Proclidæ. See SPARTA. He died For theoretical learning and sciences there is noafter a long and successful reign, during which thing yet complete. Burnet's Theory of the Earth. the Messenian war was carried on, about

Practice alone divides the world into virtuous and A. A. C. 723.

vicious; but as to the theory and speculation of vir

tue and vice, mankind are much the same. THEOR'BO, n. s. Fr. tuorbe ; Ital. tiorba.

South's Sermons. A large lute for playing a thorough bass, used by

The greatest theorists have given the preference to the Italians.

such a government as that which obtains in this He wanted nothing but a song,


Addison. And a well tuned theorbo hung

True christianity depends on fact :
Upon a bough, to ease the
Religion is not theory, but act.

Harte. His tugged ears suffered, with a strain. Butler.

ΤΗ EOSOPHISTS, froιη θεος, God and σοφια, THE’OREM, n. s. Fr. theoreme ; Greek

wisdom, a fanatical sect of philosophers, who THEOREMATIc, adj. (θεωρημα. A position

rose about the end of the sixteenth century, and THEOREMAT'ICAL, laid down as truth; pretended to derive all their knowledge from di

THEOREM'IC. comprised of or relating vine illumination. They ascribed this to the to theorems. Having found this the head theorem of all their that they were able to make such a use of the

singular manifestation of divine benevolence, discourses, who plead for the change of ecclesiastical element of fire, in the chemical art, as enabled government in England, we hold it necessary that them to discover the essential principles of the proofs thereof be weighed. The chief points of morality are

no less demon- bodies. Hence they were also called Fire-Phistrable than mathematicks; nor is the subtilty greater losophers. One of their chief leaders and ornain moral theorems than in mathematical.

was the celebrated Paracelsus, from More's Divine Dialogues. whom they were called Paracelsists. Many observations go to the making up of one THEOXENIA, a festival held annually in all theorem, which, like oaks fit for durable buildings, the cities of Greece, but chiefly al Athens, in homust be of many years growth.


nor of all the gods. Here are three theorems, that from thence we may

THERAMENES, a celebrated Athenian gedraw some conclusions. Dryden's Dufresnoy. Theoremick truth, or that which lies in the con- the Megarians, and suppressed a tumult in Athens;

neral, patriot, and philosopher. He defeated ceptions we have of things, is negative or positive.


but the Atheuians being at last completely subHer thoughts were theorems, her words a problem, jugated by the Spartans, who demolished their as if she det ed that mystery would ennoble 'em. walls and subjected them to thirty tyrants, all


under Spartan influence, except Theramenes, A THEOREM, mathematically, is a proposition who was the only one of the thirty that stood up which terminates in theory, and which considers for his country. The rest abused their power

But the properties of things already made or done; in the most cruel and arbitrary manner. or it is a speculative proposition deduced from Theramenes's patriotic opposition to these tycomparing together several definitions. A theo- rants only ended in his own death. It is said rem is something to be proved, and a problem that when he drank the bowl of poison, he

drank to the health of Critias, his accuser, but something to be done.

THEORIUS, Gr. Ocopios, i. e. clear-sighted. along with that compliment he imprecated a A surname of Apollo, at Træzene.-Lempr.

curse on the tyrant, which was soon after fulfilled. THEORY, n. s.

Fr. theorie ; Greek

THERAPEUTÆ, a term that has been vaTHEORET'ic, adj.

Sewpia. Speculation; riously applied to those that are occupied wholly THEORETICAL, scheme; plan or sys

in the service of religion. A Jewish sect was THEORETICALLY, adv. tem, yet subsisting

so called from the extraordinary purity of its reTue'oric, n. s.

only in the mind;

ligious worship. With a kind of religious not practice : the adjectives and adverb corre phrenzy, they placed their whole felicity in the spond: theoric is used by Shakspeare for theory. contemplation of the Divine nature ; and, detach

If they had been themselves to execute their own ing themselves wholly from secular' affairs, theory in this church, they would have seen, being transferred their property to their relations or nearer.

Hooker. friends, and withdrew into solitary places. How When he speaks,

long this sect continued is uncertain ; but it is The air, a chartered libertine, is still ;

not improbable that, after the appearance of And the mute wonder lurketh in men's ears, Christianity in Egypt, it soon became extinct. To steal his sweet and honied sentences :

THERAPEUẤTIC, adj. Gr. θεραπευτικος. So that the act and practick part of life

Curative; teaching or endeavouring the cure of Must be the mistress to this theorique. Shakspeare. discases.

The bookish theorick Wherein the toged consuls can propose

The practice and thrapeutick is distributed into As masterly as he; meer prattle without practice

the conservative, preservative, and curative. Is all his soldiership Id. Othello.

Harvey. In making gold, the means hitherto propounded

Therapeutick or curative physick restoreth the to effect it are in the practice full of errour, and in patient into sanity, and taketh away diseases acthe theory full of unsound imagination.

tually affecting

Browne. Bacon's Natural History.

Medicine is justly distributed into prophylactick, The theorical part of the inquiry being interwoven the art of restoring it.

or the art of preserving health ; and therapeutick, or

IVatts. with the historical conjectures, the philosophy of colours will be promoted by indisputable experiments.

THERAPNE, an ancient town of Laconia, Boyle on Colours. on the west bank of the Eurotas, where Apollo


had a temple called Phæbeum; near Lacedæmon. Germany had stricken off that which appeared Castor and Pollux were born in it, and hence corrupt in the doctrine of the church of Rome, but called Therapnæi.

seemed in discipline still to retain therewith very

Id. THERAPNE, a daughter of Lelex, king of Spar- great conformity. ta, who gave name to the above town.

Grace having not in one thing shewed itself, nor THEŘAUD, an extensive district and town for some few days, but in such sort so long con

tinued, our manifold sins striving to the contrary, of Hindostan. The town contains nearly 3000 what can we less thereupon conclude, than that God houses, and is surrounded by a wall and dry would at least-wise, by tract of time, teach the world, ditch, both in bad repair. The palace and tem- that the thing which he blesseth cannot but be of ple are lofty buildings; but the houses are sel- him?

Id. dom more than one story high. The only water For reformation of errour there were that thought to be found is drawn from wells, which are sixty it a part of christian charity to instruct them. Id. feet deep, and is brackish. The whole district is Is it in regard then of sermons only, that, apprevery dry and barren. The regular revenues of hending the gospel of Christ, we yield thereunto our the chief are said to be only 20,000 rupees per unfeigned assent as to a thing infallibly true ? Id.

Therein our letters do not well agree. Shakspeure.

This is the last parley we will admit; THERE, adv.

Therefore to our best mercy give yourselves. Id. THERE'ABOUT,

You shall bereave yourself THERE'A BOUTS,

of my good purposes, and put your children THEREAFTER,

To that destruction which I'll guard them from, THEREAT,

If thereon you rely. Id. Antony and Cleopatra. Thereby',

Goth. thar ; Sax. ten; To see thee fight, to see thee traverse, to see thee THEREFORE, Dan. der ; Belg. daar. In here, to see thee there.

Id. Merry Wres. Therefrom', that place; opposed to Well, give her that ring, and give therewithul

That letter.

Id. Two Gentlemen of Verona.
THEREIN', here; and, in composition,
THEREINTO', >often meaning that, as

If they come to sojourn at my house,
I'll not be there.

Id. King Leur.
THEREOF', therefrom means from that
Thereon', (i. e. place), and this with And thereupon he sends you this good news.

He hopes to find you forward, TIEREOUT, the extracts will explain

Shukspeute. THERETO', the principal compounds One speech I loved, 'twas Æneas's tale to Dido, THEREUNTO',

and thereabout of it especially, where he speaks of THEREUNDER',

Priam's slaughter.

Id. Hamlet. THEREUPON',

Those which come nearer unto reason find a paraTHEREWITH',

dise under the equinoctial line, judging that thereunTHEREWITHAL'.

der might be found most pleasure, and the greatest fertility.

Raleigh. Be ye therefore very courageous to do all that is The matter is of that nature, that I find myself wrilten in the law, that ye turn not aside therefrom, unable to serve you therein as you desire. Bacon. . to the right hand or to the left. Jos. xxiii. 6. Though we shall have occasion to speak of this,

Wide is the gate, and broad is the way that lead- we will now make some entrance thereinto. Id. eth to destruction, and many go in thereut.

All things without, which round about we see, Matt. vii. 13.

We seek to know, and have therewith to do. We have forsaken all and followed thee, what

Davies. shall we have therefore?

Id. xix. 27. Between the twelfth of king John, and thirty-sixth Peter called to mind the word that Jesus said ; of king Edward the third, containing one liunared and when he thought thereon he wept.

and tilty years or thereabouts, there was a continual Mark xiv. 72. bordering war.

Id. As they were much perplexed thereabout, two men Though grants of extraordinary liberties made by stood by.

Luke xxiv. 4.

a king to his subjects do no more diminish his greatLet nor them that are in the countries enter there.

ness than when one torch lighteth another, yet many into.

Luke. times inconveniencies do arise thereupon. Therewith at last he forced him to untie

Id. on Ireland. One of his grasping feet, him to defend thereby. Being come to the height, they were thereby Spenser. brought to an absolute necessity.

Id. His hideous tail then hurled he about,

Within ourselves, we strangers are thereto. And therewithal enwrapt the nimble thighs

Davies. Of his froth-foamy steed.


When you can draw the head indifferently well, Thereout a strange beast with seven heads arose,

proportion the body thereafter.

Peacham. That towns and castles under her breast did cour. Some three months since, or thereabout, Id. She found me out.

Suckling. Next thereunto did grow a goodly tree,

There have been that have delivered themselves That whereby we reason, live, and be.


from their ills by their good fortune or virtue. ld. Considering how the case doth stand with this

Dare to be true ; nothing can need a lie ; present age, full of tongue and weak of brain, be. A fault which needs it must grow two thereby. hold we yield to the stream thereof. Hooker.

Herbert. Every errour is a stain to the beauty of nature ; There are delivered in holy scripture many weighty for which cause it blusheth thereat, but glorieth in arguments for this doctrine.

White. the contrary.

Id. In human actions there are no degrees described, Some parts of our liturgy consist in the reading of but a latitude is indulged. Bishop Taylor. the word of God, and the proclaiming of his law, Therewithal the execrable act that the people may thereby learn what their duties on their late murthered king they aggravate. are towards him. Id.



epon them.

What might his force have done being brought THERMÆ, hot baths or bagnios. Luxury therelo,

and extravagance were in nothing carried to When that already gave so much to do?


such heights as in the thermæ of the Roman emThere cannot in nature be a strength so great, as

perors. Ammian complains that they were to make the least moveable to pass in an instant, or built to such an extent as to equal whole proall together, through the least place.

vinces; from which Valesius would abate, by Digby on the Soul.

reading piscinæ instead of provinciæ. And yet, 'Tis vain to think that lasting which must end ;

after all, the remains of some still standing are And when 'tis past not any part remains

sufficient testimonies for Ammian's censure; and Thereof. but the reward which virtue gains.

Denham, the accounts transmitted of their ornaments and Darkness there might well seem twilight here.

furniture, such as being laid with precious stones

Milton. (Seneca), set round with seals of solid silver Find a house to lodge a hundred and fifty persons, (Pliny), with pipes and cisterns of the same mewhereof twenty or thereabouts may be attendants. tal (Statius), add to, rather than take from, the


The most remarkable bagnios were If food were now before thee set,

those of Dioclesian and Caracalla at Rome, great Wouldst thou not eat ? thereafter as I like

part of which remain at this day; the lofty The giver.


arches, stately pillars, variety of foreign marble, All the earth

curious vaulting of the roofs, great number of To thee and to thy race I give ; as lords Possess it, and all things that therein live. Id.

spacious apartments, all attract the curiosity of A larger form of speech were safer than that the traveller. They had also their summer and

winter baths. See BATHING. which punctually prefixeth a constant day thereto.


THERMÆ SELINUNTIÆ, an ancient town of That it is the appointment of God, might be argu- Sicily, near Selinus, famous for its hot baths; ment enough to persuade us thereunto. Tillotson. now called Sciacca. See SCIACCA. Your fury hardens me,

THERMÆUS Sinus, a bay of Macedon, on i guard there ; seize her. Dryden's Aurengsebe. the coast of Therma or Thessalonica, afterwards

After having well examined them, we shall therein called Sinus Macedonicus.-Strabo. find many charms.

Dryden's Dufresnoy.

THERMIDOR, the eleventh month in the Children are chid for having failed in good man: Revolutionary French calendar. It begins on ners, and have thereupon reproofs and precepts heaped the 19th July, and ends on the 17th August.


THERMODON, a river of ancient Bæotia, The leaves that spring therefrom grow white.


near Tanagra, called also Hæmon.-Strabo 11. He blushes, therefore he is guilty. Spectator.

TAERMODON or THERMODOON, a river of CapIf the paper be placed beyond the focus, and then padocia in the country of the Amazons; running the red colour at the lens be alternately intercepted into the Euxine Sea, near Themiscyra. It is and let pass, the violet on the paper will aot suffer now called Termeh. any change thereby.

Newton. THERMOM'ETER, n. s. Fr. thermome. Exiled by thee from earth to deepest hell,

THERMOMET'RICAL, adj. I tre; Gr. Jeppos In brazen bonds shall barbarous discord dwell;

and perpov. An instrument for measuring the Gigantic pride, pale terror, gloomy care,

heat of the air, or of any matter : relating to the And mad ambition shall attend her there. Pope.

measure of heat. Solon finding the people engaged in two violent

The greatest heat is about two in the afternoon, factions, of the poor and the rich, and in great confusion thereupon, made due provisions for settling the thermometer, or observations of the weather-glass.

when the sun is past the meridian, as is evident from the balance of power. Swifi.

Browne, The wrestlers sprinkled dust on their bodies to

His heat raises the liquor in the thermometrical give better hold : the glory therefore was greater to tubes.

Cheyne. conquer without powder.

West's Pindar.

THERMOMETER. This instrument was inTHERESIENSTADT, or MARIEN THERE- vented about the beginning of the seventeenth cenSIENSTADT, a large town of the south of Hun- tury; but, like many other useful inventions, it gary, in the palatinate of Bacs. In fact it is an has been found impossible to ascertain to whom assemblage of villages, consisting of perhaps the honor of it belongs. Boerhaave ascribes it 3000 cottages, inhabited by 22,000 inmates, to Cornelius Drebbel of Alcmaer, his own counpartly of Servian, partly of Rascian descent. tryman. Fulgenzio attributes it to his master They depend for their support chiefly on the Paul Sarpi, the great oracle of the Venetian reextensive town lands, the total extent of which public; and Viviani gives the honor of it to Gais said to be 340 square miles. The town is lilæo. But all these are posthumous claims. open, but has large barracks, a Catholic church Sanctorio claims this honor to himself; and his for the Servians, a Greek for the Rascians, and assertion is corroborated by Borelli and Mala Franciscan monastery for Catholics; these pighi, of the Florentine academy, whose parcomplete the list of its public buildings. The- tiality is not to be suspected in favor of a member resienstadt has a pretty active traffic in cattle, of the Patavinian school. Perhaps the best way horses, wool, and hides.

to reconcile these different claims would be to THERI'ACAL, adj. Gr. Impiaka; Lat. the- suppose that the thermometer was really invented riacu. Medicinal; physical.

by different persons about the same time. The virtuous bezoar is taken from the beast thai A common thermometer consists of a tube feedeth upon the mountains where there are theriacal terminated at one end by a bulb, and closed at herbs.

Bacon. the other. . ] he bulb and part of the tube are

filled with a proper liquid, generally mercury, The correction in this table is expressed in and a scale is applied, graduated into equal parts. 1000th parts of the distance between the freezWhenever this instrument is applied to bodies of ing point and the surface of the ice : e.g. if the the same temperature, the mercury being simi- freezing point stands seven inches above the larly expanded, indicates the same degree of surface of the ice, and the heat of the room is heat.

62°, the point of 32° should be placed 7 x 00261, In dividing the scale of a thermometer, the or •018 of an inch lower than the observed point. two fixed points usually resorted to are the A diagonal scale will facilitate this correction. freezing and boiling of water, which always The committee observe that, in trying the heat of takes place at the same temperature, when under liquors, care should be taken that the quicksilver the same atmospheric pressure. The interme- in the tube of the thermometer be heated to the diate part of the scale is divided into any con same degree as that in the ball: or, if this cannot venient number of degrees; and it is obvious be done conveniently, the observed heat should that all thermometers, thus constructed, will in- be corrected on that account; for the manner of dicate the same degree of heat when exposed to doing which, and a table calculated for this purthe same temperature. In the centigrade ther- pose, we must refer to their excellent report in mometer this space is divided into 100°; the the Phil. Trans., vol. LXVII., part ii., article freezing of water being marked 0°, the boiling 37. With regard to the choice of tubes, they point 100°. In this country we use Fahrenheit's ought to be exactly cylindrical. But, though the scale, of which the 0° is placed at 32° below the diameter should vary a little, it is easy to manage freezing of water, which, therefore, is marked that matter in the manner proposed by the abbé 32°, and the boiling point 212°, the intermediate Nollet, by making a small portion of the quickspace being divided into 180°. Another scale is silver, e.g. as much as fills up an inch or half Reaumur's, the freezing point is 0°, the boiling an inch, slide backward and forward in the tube; point 80°. These are the principal thermometers and thus to find the proportions of all its ineused in Europe. It may be proper to state that qualities, and thence to adjust the divisions to a the spirit of wine thermometer is usually em- scale of the most perfect equality. The capilployed for very low temperatures, as mercury lary tubes are preferable to others, because they may be frozen in the atmosphere ; whilst mer- require smaller bulbs, and they are also more cury, on the contrary, is best calculated for high sensible, and less brittle. The most convenient temperatures, as its point of ebullition is little size for common experiments has the internal short of a red heat.

diameter about the fortieth or fiftieth of an inch, The Royal Society, fully apprised of the im- about nine inches long, and made of thin glass portance of adjusting the fixed point of ther- that the rise and fall of the mercury may be better mometers, appointed a committee of seven seen. The next thing to be considered is of gentlemen to consider of the best method for what number of degrees or divisions the scale this purpose; and their report is published in ought to consist, and from what point it ought the Phil. Trans. vol. LXVII., part ii., article 37. to commence. As the number of the divisions They observed that, though the boiling point be of the scale is an arbitrary matter, the scales placed so much higher on some of the ther- which have been employed differ much from one mometers now made than on others, yet this another in this circumstance. Fahrenheit has does not produce any considerable error in the made 180° between the freezing and boiling observations of the weather, at least in this cli- water point. Amontons made 73°, and sir Isaac mate; for an error of 1° 30', in the position of Newton only 34o. There is, however, one genethe boiling point, will make an error only of half ral maxim, which ought to be observed : that a degree in the position of 92°, and of not more such an arithmetical number should be chosen than a quarter of a degree in the point of 62o. as can easily be divided and subdivided, and It is only in nice experiments, or in trying the that the number of divisions should be so great heat of hot liquors, that this error in the boiling that there shall seldom be occasion for fractions. point can be of much importance. In adjusting The number eighty, chosen by Reaumur, answers the freezing as well as the boiling point, the extremely well in this respect, because it can quicksilver in the tube ought to be kept of the be divided by several figures without leaving a same heat as that in the ball. When the freezing remainder; but it is too small a number : the point is placed at a considerable distance from consequence of which is that the degrees are the ball, the pounded ice should be piled to such placed at too great a distance from one another, a height above the ball that the error which can and fractions must therefore be often employed. arise, from the quicksilver in the remaining part We think therefore that 160 would have been a of the tube not being heated equally with that in more convenient number. Fahrenheit's number the ball, shall be very small, or the observed 180 is large enough; but, when divided, its point must be corrected on that account accord- quotient soon becomes an odd number. As to ing to the following table :

the point at which the scale ought to commence,

various opinions have been entertained. If we Heat of Air. Correction.

knew the beginning or lowest degree of heat, all

philosophers would agree that the lowest point of 42° .00087

the thermometer ought to be fixed there; but we 52 00174

know neither the lowest nor the highest degrees 62 00261

of heat; we observe only the intermediate parts. 00348

All that we can do then is to begin it at some 82 '00435

invariable point, to which thermometers made in different places_may easily be adjusted. If pos


sible, too, it ought to be a point at which a Reaumur.

Fahrenheit. natural well known body receives some re 16° X 9= 144 4= 36 + 32° = 68. markable change from the effects of heat or cold. 80° X 9 = 720 • 4 = 180 + 32o = 212. Fahrenheit began his scale at the point at which

Every degree of Fahrenheit is equal to fivesnow and salt congeal. Kirwan proposes the ninths of a degree on the centigrade scale; the freezing point of mercury. Sir Isaac Newton, reduction, therefore, is as follows :Hales, and Reaumur, adopted the freezing point Fahrenheit.

Centigrade. of water. The objection to Fahrenheit's lowest 212° — 32 = 180 x 5 = 900 + 9 = 100°. point is that it commences at an artificial cold never known in nature, and to which we cannot


Fahrenheit. refer our feelings; for it is what few can ever ex

100 x 9 = 900; 5 = 180 x 32 = 212°. perience. There would be several great advan M. Bellani has proved, by reference to direct tages gained, we allow, by adopting the freezing experiment, that a mercurial thermometer made in point of mercury. It is the lowest degree of the usual manner, and the freezing point of water cold to which mercury can be applied as a mea- marked on it from experiment, if it be laid aside sure; and it would render unnecessary the use of awhile, and again plunged in melting ice, the the signs plus and minus, and the extension of mercury will stand higher than before; and that the scale below 0. But we object to it that it is if it be put aside again, and then again tried, the not a point well known; for few, comparatively mercury will be higher still, until, at the end of a speaking, who use thermometers, can have an certain time, a year or so, the effect of elevation opportunity of seeing mercury congealed. As will cease. to the other advantage to be gained by adopting It was found, from numerous experiments, that the freezing point of mercury, namely the aboli- the result was not influenced by the various quation of negative numbers, we do not think it lities of the glass used in the instrument; by the would counterbalance the advantage to be en more or less perfect exclusion of air from the joyed by using a well known point. Besides, it bulb or tube ; by the constant horizontal, permay be asked, Is there not a propriety in using pendicular, or inverted position of the instrunegative numbers to express the degree of cold, ment; by the open or closed extremity; hy the which is a negative thing? Heat and cold we longer or shorter time of remaining in the ice; or can only judge of by our feelings : the point then by the compression of the surrounding ice. at which the scale should commence ought to be Neither was it found to be peculiar to mercurial a point which can form to us a standard of heat thermometers, but was exhibited by alcohol therand cold; a point familiar to us, from being one mometers, though in a less degree. of the most remarkable that occurs in nature, M. Bellani at last ascertained that the effect and therefore a point to which we can with most was due to a gradual and slow contraction of the clearness and precision refer in our minds on glass after having been highly heated, which conall occasions. This is the freezing point of water traction, as long as it continued, diminished the chosen by sir Isaac Newton, which of all the bulk of the instrument, and consequently forced general changes produced in nature by cold is the fluid into the tube. This effect he illustrates the most remarkable. It is therefore the most in the following manner :- Take a Florence flask, convenient point for the thermometers to be used or any similar thin glass vessel, such as a matrass in the temperate and frigid zones; we may say with a long narrow neck, shortly after it has over the globe, for even in the hottest countries come from the glass furnace, it not having been of the torrid zone many of the mountains are annealed in the oven; introduce shot or sand perpetually covered with snow.

into it till it almost sinks in water, seal it hermeThe principal thermometric scales in Europe tically, and draw out one part of the neck until are, as we have already stated, Fahrenheit's, not more than a line in diameter, that part being which commences at the temperature produced about an inch in length; fasten a small basin on by mixing snow and salt, and which is 32° below the top of the neck with wax, and then, putting the freezing of water, so that the latter point is the instrument in water of a certain temperature, marked 32°, and the boiling point 212°, the in- 40° Fahrenheit, for instance, put weights in the termediate space being divided into 172°; Reau- cup till the surface of the water is at the middle mur's, in which the zero is the freezing point, of the narrow part of the neck; then lay the instruand 80° the boiling point; and the centigrade, ment aside for some days, or better still some weeks in which the space between the freezing and boil- or months, and, after that time, again immerse ing of water is divided into 100°.

it in the same water at the same temperature and Each degree of Fahrenheit's scale is equal to pressure, and with the same weight; the instrufour-ninths of a degree on Reaumur's; if, there- ment will now sink lower than before, in consefore, the number of degrees on Fahrenheit’s quence of its diminished bulk from gradual conscale, above or below the freezing of water, be traction of the glass. multiplied by four, and divided by nine, the It was found that, although the effect was greatquotient will be the corresponding degree of est after the glass had been rendered soft by heai, Reaumur.

yet that it occurred also when the elevation of Fahrenheit,

Reaumur. temperature had not extended nearly to the soft68°– 32° = 36 x 4 = 144 : 9 = 16°. ening of the glass, and indeed more or less upon 212° — 32° = 180 X 4 = 720 = 9= 80°. every rise of temperature. Hence two kinds of

To reduce the degrees of Reaumur to those of irregularity in thermometers arise from the same Fahrenheit, they are to be multiplied by nine, cause. The one is manifested soon after the forand divided by four.

mation of the instrument, increases to a certain lol. XXII.


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