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ment and Desormes regards carbonic acid, which, body, in cooling a certain thermometric range at being reduced to the standard of weights, gives a high temperature, gives out the same quantity a specific heat compared to air of about 0:987 to of heat that it does in cooling through the same 1.000, while oxygen is only 0.9000. The former range at a lower temperature? No means seem tables of Crawford and Dalton give the specific better adapted for solving this problem, than to heat of oxygen 2:65, and of carbonic acid 0.586, measure the refrigeration produced, by the same compared to air 1.000. · And, upon these very weights of ice, on uniform weights of water, at erroneous numbers, they reared their hypothe different temperatures. Mr. Dalton found in tical fabric of latent heat, combustion, and the this way, that * 176.5° expresses the number of animal temperature.

degrees of temperature, such as are found We see from the experiments on air, at dif- between 200° and 212° of the old or common ferent densities, that its specific heat diminishes scale, entering into ice of 32° to convert it into in a much slower rate than its specific gravity. water of 32°; 150° of the same scale, between When air is expanded to a quadruple volume, 122° and 130°, suffice for the same effect; and its specific heat becomes 0.540, and, when ex- between 45o and 50°, 128° are adequate to the panded to eight times the volume, its specific conversion of the same ice into water. These heat is 0.368. The densities in the geometrical three resulting numbers (128, 150, 176-5), are progression 1, 1, 1, , correspond nearly to the nearly as 5, 6, 7. Hence it follows, that as specific heats in the arithmetical series 5, 4, much heat is necessary to raise water 5° in the 3, 2. Hence also the specific heat of atmo- lower part of the old scale, as is required to spherical air, and of probably all gases, consi- raise it 7° in the higher, and 6° in the middle.' dered in the ratio of its weight or mass, dimi- See his New System of Chemical Philosophy, nishes as the density increases. On the principle vol. i. p. 53. of the increase of specific heat, relative to its “Mr. Dalton, however,' says Dr. Ure, ‘instead mass, has been explained the long observed phe- of adopting the obvious conclusion, that the capanomenon of the intense cold which prevails on city of water for heat is greater at lower than it the tops of mountains, and generally in the is at higher temperatures, and that therefore a upper regions of the atmosphere; and also that smaller number of degrees at the former should of the prodigious evolution of heat, when air is melt as much ice as a great number at the latter, forcibly condensed. According to M. Gay Lus- ascribes the deviation denoted by these numbers, sac, a condensation of volume, amounting to 5, 6, and 7, to the gross errors of the ordifour-fifths, is sufficient to ignite tinder. If a nary thermometric graduation, which he consisyringe of glass be used, a vivid flash of light is ders so excessive, as not only to equal, but seen to accompany the condensation.

greatly to overbalance the really increased spe

cific heat or capacity of water; which, viewed in Table IV.–Of Specific Heats of some Solids itself, he conceives would have exhibited oppodetermined by Dulong and Petit. site experimental results. That our old, and,

according to his notions, obsolete thermometric Specific Weight of Product

scale, has no such prodigious deviation from heats, that the atoms, of these

truth, is, I believe, now fully admitted by cheof water oxygen be- two num

mical philosophers; and therefore the only legibeing 100.

bers. timate inference from these very experiments of

Mr. Dalton is the decreasing capacity of water, Bismuth

0.0288 13:300 0.3830 with the increase of its temperature. It deserves Lead

0·0293 12.950 0.3794 to be remarked, that my experiments on the Gold

0.0298 12:430 0.3704 relative times of cooling a globe of glass, succesPlatinum 0.0314 11.160 0.3740 sively filled with water, oil of vitriol, common Tin

0.0514 7.350 0:3779 oil, and oil of turpentine, give exactly the same Silver,

0.0557 6.750 0.3759 results as Mr. Dalton had derived from mixtures Zinc

0:0927 4.030 0.3736 of two ounces of ice with sixty of water, at difTellurium 0·0912 4.030 0:3675 ferent temperatures. This concurrence is the more Copper 0.0949 3.957 0.3755 satisfactory, since, when my paper on the speNickel

0:1035 3.690 0:3819 cific heats of the above bodies, published in the Iron

0 1100 3.392 0.3731 Annals of Philosophy for October 1817, was Cobalt

0:1498 2.460 0.3685 written, I had no recollection of Mr. Dalton's Sulphur 0.1880 2.011 0.3780 experiments.'

Table V.-Of Capacities for Heat. The above products, which express the capa

Mean capacity cities of the different atoms, approach so near

Mean capacity between

between 0° and

00 and 1000 equality, that the slight differences must be owing

3000°. to slight errors, either in the measurement of the capacities, or in the chemical analyses, especially Mercury 0.0330

0.0350 if we consider, that, in certain cases, these errors, Zinc

. 0.0927

0.1015 derived from these two sources, may be on the Antimony

0.0507

0·0549 same side, and consequently be found multiplied Silver

. 0·0557

0.0611 in the result. Each atom of these simple bodies Copper . 0·0949

0.1013 seems, therefore, as was formerly stated, to have Platinum 0.0355

0.0355 the same capacity for heat.

Glass
. 0:1770

0.1900 The question may here be asked, Whether a

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The capacity of iron was determined at the elevation of their temperature, that it becomes four following intervals :

an easy task to ascertain within certain limits From 0 to 100°, the capacity is 0·1098

the augmentation of volume which liquids and 0 to 200

0:1150

gases suffer through a moderate thermometric 0 to 300

0.1218

range. We have only to enclose them in a glass

0.1255 0 to 350

vessel of a proper form, and expose it to heat.

But to determine their expansion with final ac*If we estimate, continues Dr. Ure, the curacy, and free the results from the errors temperatures, as some philosophers have pro- arising from the unequable expansion of the reposed, by the ratios of the quantities of beat cipient, is a problem of no small difficulty. It which the same body gives out in cooling to a seems, however, after many vain attempts by determinate temperature, in order that this cal- preceding experimenters, to have been finally culation be exaci, it would be necessary that the solved by MM. Dulong and Petit. The expanbody in cooling, for example, from 300° to 0°, sion of 'solids had been previously measured should give out three times as much heat as in with considerable accuracy by several philosocooling from 100° to 0°, But it will give out phers, particularly by Smeaton, Roy, Ramsden, more than three times as much, because the and Troughton, in this country, and Lavoisier capacities are increasing. We should therefore and Laplace in France. The method devised find too high a temperature. We exhibit in the by general Roy, and executed by him in confollowing table the temperatures that would be junction with Ramsden, deserves the preference. deduced by employing the different metals con- The metallic or other rod, the subject of experitained in the preceding table, We must suppose ment, was placed horizontally in a rectangular that they have been all placed in the same liquid trough of water, which could be conveniently bath at 300°, measured by an air thermometer. heated. At any aliquot distance on the rod, Iron

332-20 two micrometer microscopes were attached at Mercury

318.2 right angles, so that each being adjusted at first Zinc

328.5 to two immoveable points, exterior to the heating Antimony

92468

apparatus, when the rod was elongated by heat, Silver

329.3.

the displacement of the microscopes could 'be Copper

320-0 determined to a very minute quantity, to the · Platinum

317.9 twenty or thirty thousandth of an inch, by the Glass

322:1

micrometrical mechanism. PART II.

Dr. Ure, in the years 1812 and 1813, made,

he tells us, many experiments with a micromeOF THE GENERAL SYMPATHIES OF HEAT trical apparatus of a peculiar construction, for WITH THE DIFFERENT FORMS OF MATTER. measuring the dilatation of solids. I was par

The effects of heat are either transient and ticularly perplexed,' he says, 'with the rods or physical, or permanent and chemical, inducing zinc, which, after innumerable trials, I finally a durable change in the constitution of bodies. found to elongate permanently by being alterThe latter effect we have already treated of in nately heated and cooled. It would seem that our article COMBUSTION. The first is to be dis- the plates composing this metal, in sliding over cussed here; and divides itself into the two each other by the expansive force of heat, present heads, of changes in the volume of bodies while such an adhesive frietion as to prevent their enthey retain their form, and changes in the state tire retraction. It would be desirable to know of bodies.

the limit of this effect, and to see what other 1. The successive increments of volume which metals are subject to the same change. - I hope bodies receive with successive increments of to be able, ere long, to finish these pyrometrical temperature, have been the subjects of innumer- researches.' The doctor then gives us the folable researches. The expansion of fluids is so lowing copious tables of dilatations, compiled much greater than that of solids, by the same from the best experiments :

Table I.—Linear Dilatation of Solids by Heat.
Dimensions which a bar takes at 2120, whose length at 320 is 1.000000.

Dilatation

in Vulgar Glass tube,

Smeaton,

1.00083333 Fractions, Do.

Roy,

1.00077615

1.00082800 Do.

Dulong and Petit,

1.00086130 Do.

Lavoisier and Laplace, 1.00081166
Do.
do.

1.000890890
crown glass,

Do.
do.

1:00087572
Do.
do.

1.00089760
Do.
do.

Do.
do.

1.00091751
Roy,

1.00080787 Deal,

Roy, as glass, Platina,

Borda,

1.00085655 Do.

Dulong and Petit,

1.00088420 Do.

Troughton,

1.00099180 Do. and glass,

Berthoud,

1.00110000 Palladium,

Wollaston,

1.00100000

Do.

Deluc's mean,

TITO
TT18

Plate glass,
Do.
Do.

1

do.

1 TCT

Do. rod,

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807

613

TABI E I.—Linear Dilatation of Solids by Ileat.- Continued
Dimensions which a bar takes at 212°, whose length at 32° is 1.000000. Dilatation

in Vulgar Antimony,

Smeaton,

1.00108300

Fractions. Cast iron prism,

Roy,

1.00110940
Cast iron,

Lavoisier, by Dr. Young, 1.00111111
Steel,

Troughton,

1.00118990 Steel rod,

Roy,

1.00114470
Blistered steel,

Phil. Trans. 1795, 428, 1.001 12500
Do.

Smeaton,

1.00115000
Steel not tempered,

Lavoisier and Laplace, 1.00107875
Do. do. do.

Do.
do.
1.00107956

926 Do. tempered yellow,

Do.
do.

1.00136900
Do. do. do.

Do.
do.

1.00138600
Do. do. do. at a higher heat, Do.

do.

1.00123956 Steel,

Troughton,

1.001 18980 Hard steel,

Smeaton,

1.00122500 Annealed steel,

Muschenbroex,

1.00122000 Tempered steel.

Do.

1.00137000 Iron,

Borda,

1.00115600 Do.

Smeaton,

1.00125800 Soft iron forged,

Lavoisier and Laplace,

1.00122045
Round iron, wire-drawn,

Do.
do.

1.90123504
Iron wire,

Troughton,

1.00144010 Iron,

Dulong and Petit,

1.00118203

513 Bismuth,

Smeaton,

1:00139200 Annealed gold,

Muschenbroek,

1.00146000
Gold,

Ellicot, by comparison, 1.00150000
Do.' procured by parting,

Lavoisier and Laplace,

1.00146606 Do. Paris standard, unannealed, Do.

do.

1.00155155
Do. do. annealed,

Do.
do.
1.00151361

661 Copper,

Muschenbroek,

1.0019100 Do.

Lavoisier and Laplace,

1.00172244

31 Do.

Do.
do.
1.00171222

384 Do.

Troughton,

1.00191880 Do.

Dulong and Petit,

1.00171821 ਝਉਣ Brass,

Borda,

1.00178300
Do.

Lavoisier and Laplace, 1.00186671
Do.

Do.
do.

1.04188971
Brass scale, supposed from Hamburg, Roy,

1.00185540 Cast brass,

Smeaton,

1.00187500 English plate-brass, in rod,

1.00189280 Do. do. in a trough form, Do.

1.00189490 Brass,

Troughton,

1.00191880 Brass wire,

Smeaton,

1.00193000 Brass,

Muschenbroek,

1.00216000 Copper 8, tin 1,

Smeaton,

1.00181700 Silver,

Herbert,

1.00189000
Do.

Ellicot, by comparison, 1.0021000
Do.

Muschenbroek,

1.00212000
Do, of cupel,

Lavoisier and Laplace, 1.00190974
Do. Paris standard,

do.

1.00190868 Silver,

Troughton,

1.0020826 Brass 16, tin 1,

Smeaton,

1.00190800 Speculum metal,

Do.

1.00193300 Spelter solder; brass 2, zinc 1, Do.

1.00205800 Malacca tin,

Lavoisier and Laplace, 1.00193765 512
Tin from Falmouth,

Do.
do.

1.00217298
Fine pewter,

Smeaton,

1.00228300 Grain tin,

Do.

1.00248300 Tin,

Muschenbroek,

1.00284000 Soft solder; lead 2, tin 1,

Smeaton,

1.00250800 Zinc 8, tin 1, a little hammered, Do

1.00269200
Lead,

Lavoisier and Laplace, 1.00284836
Do.

Smeaton,

1.00286700 Zinc,

Do.

1.00294200 Zinc, hammered out į inch per foot, Do.

1.00301 100 Glass, from 32° to 212°,

Dulong and Petit

1.00086130
Do. from 212°, to 392°,

Do.
do.
1.00091827

TONG
Do. from 392°, to 572°,

Do.
do.
1.000101114

957 The last two measurements by an air thermometer.

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Roy,

Do.

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Table II.–Dilatation of the volume of Liquids by being heated from 32° to 212o.

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Mercury, Dalton

Do. Lord Charles Cavendish
Do. Deluc
Do.

General Roy
Do. Shuckburgh
Do.

Lavoisier and Laplace
Do. Haellstrøm
Do.

Dulong and Petit
Do, do. from 211°, to 392°
Do. do. from 392', to 572° .
Do.

do. in glass, from 32°, to 212°
Do. do.

do. from 212°, to 392°
Do. do. do. from 392°, to 572°
Water, Kirwan, from 39°, its maximum density
Muriatic acid (sp. gr. 1•137) Dalton,
Nitric acid (sp. gr. 1.40),

do.
Sulphuric acid (sp. gr. 1.85),
Alcohol,

do.
Water,

do. Water saturated with common salt, do. Sulphuric ether,

do. Fixed oils,

do.
Oil of turpentine,

do.
The quantities given by Mr. Dalton are probably too

great, as is certainly the case with mercury ; his ex-
periments being perhaps modified by his hypothetical

notions.
Water saturated with common salt, Robison

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Dr. Young, in his valuable Catalogue Raisonnée, Natural Philosophy, vol. ii. p. 391, gives the following table of the expansions of water, constructed from a collation of experiments by Gilpin, Kirwan, and Achard. He says that the degrees of Fahrenheit's thermometer, reckoning either way from 39°, being called f, the expansion of water is nearly expressed by 2282 (1 — ·0027) in 10 millionths; and the diminution of the sp. gr. by •0000022/" - ·0000000047213 This equation, as well as the table, is very important for the reduction of specific gravities of bodies, taken by weighing them in water.

102 10.99246 Kirwan 0.00754
122 0.98757

0.01243
0.98872 Deluc 0.01128
142 0.98199 K. 0.01801
162 0.97583

0.02417 167 0.97480 Deluc 0.02520 182 0.96900 K. 0:03100 202 0.96145

0.03855 212 0.95848

0:04152

0.01833 0·02481

0.03198 0.04005 0.04333

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M. Gay Lussac has lately endeavoured to discover some law which should correspond with the rate of dilatation of different liquids by heat. For this purpose, instead of comparing the dilatations of different liquids, above or below a temperature uniform for all, he set out from a point variable with regard to temperature, but uniform as to the cohesion of the particles of the bodies; namely, from the point at which each liquid boils under a given pressure. Among those which he examined, he found two which dilate equally from that point, viz. alcohol and sulphuret of carbon, of which the former boils at 173.14°, the latter at 115.9°, Fahrenheit. The other liquids did not present, in this respect, the same resemblance. Another analogy of the above two liquids is, that the same volume of each gives, at its boiling point, under the same atmospheric pressure, the same volume of vapor; or, in other words, that the densities of their vapors are to each other as those of the liquids at their respective boiling temperatures. The following table shows the results of this distinguished chemist :

0.00299
0.00321
0.00389
0.00491
0.00692

Table of the Contractions of 1000 parts in volume, by cooling.

Water.

Alcohol.

Sulphuret of Carb.

Ether.

Contract Ditto Contract Ditto Contract Ditto Contract

Ditto by expt. calculated. by expt. calculated. by expt. calculated. by expt. calculated.

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96

Their respective boiling points are:

some to apply than the above ru.e. Vapors, Water

100°

Cent. = 212° F. when heated out of contact of their respective Alcohol

78.41

173 liquids, obey the same law as gases ; a discovery Sulphuret of carb. 46.60

126 due to M, Gay Lussac. Sulphuric ether 35.66

2. Of the change of state produced in bodies by The experiments were made in thermometer caloric.—The three forms of matter, the solid, vessels hermetically sealed.

liquid, and gaseous, seem immediately referrible Alcohol, at 78:41° cent., produces 488:3 its to the power of heat, modifying, balancing, or volume of vapor.

subduing cohesive attraction. The system of Suiphuret of carbon, at 46.60° cent., produces the world presents magnificent effects of attrac491.1 'its volume of vapor.

tion dependent on figure. Such are the phenoEther, at 35.66° cent., produces 285.9 its mena of nutation and the precession of the volume of vapor.

equinoxes, produced by the attractions of the Water, at 100.00° cent., produces. 1633-1 its sun and moon on the flattened spheroid of volume of vapor.

the earth. These sublime phenomena would Mr. Dalton has the merit of having first not have existed had the earth been a sphere: proved that the expansions of all aëriform bodies, they are connected with its oblateness and rotawhen insulated from liquids, are uniform by the tion, in a manner which may be mathematically same increase of temperature; a fact of great deduced, and subjected to calculation. The inimportance to practical chemistry, which was vestigation shows, that this part of the attraction fully verified by the independent and equally dependent on figure decreases more rapidly original researches of M. Gay Lussac on the than the principal force. The latter diminishes subject, with a more refined and exact apparatus. as the square of the distance; the part dependThe latter philosopher demonstrated that 100 in ent on figure diminishes as the cube of the volume at 32° Fahrenheit, or 0° cent., became distance. Thus also, in the attractions which 1.375 at 212° Fahrenheit, or 100° cent. Hence hold the parts of bodies united, we ought to exthe increment of bulk for each degree Fahrenheit pect an analogous difference to occur. Hence is set = 0.002083 = jk; and for the centigrade the force of crystallisation may be subdued, bescale it is = 0.00375 =

To reduce any

fore the principal attractive force is overcome. volume of gas, therefore, to the bulk it would When the particles are brought to this distance, occupy at any standard temperature, we must they will be indifferent to all the positions which multiply the thermometric difference in degrees they can assume round their centre of gravity; of Fahrenheit by 0·002083, or aku, subtracting the this will constitute the liquid condition. We product from the given volume, if the gas be

must now content ourselves with stating the reheated above, but adding it, if the gas be cooled sults as much as possible in a tabular form. below, the standard temperature. Thus twentyfive cubic inches at 120° Farenheit will at 60° Taele of the Concreting or Congealing Temoccupy a volume of 217; for to X 60 = - 9 = b;

peratures of various Liquids by FAHRENHEIT'S

Scale. and =3, which, taken from 25, leaves 217. A table of reduction will be found under Gas. Sulphuric ether.

46° When the table is expressed decimally, indeed, Liquid ammo to six or seven figures, it becomes more trouble. Nitric acid, sp. gr.

1.424 40.5 Vol. \I.

J

0'375

100

266'6

46

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