E XP

EXP 555

number of liquids has been tried to ascertain whether any of them,like water, have a temperature in which their density is a maxi-mum, and which expand when cooled below that temperature.Sulphuric acid has no such point, neither have the oily bodies ; butsome solutions of salt in water begin to expand before they becomesolid. These solutions, however, when cooled down sufficiently,crystallize with such rapidity, that it is extremely difficult to be cer-tain of the fact, that they do begin to expand before they crystallize.That class of bodies which undergo an expansion when they changefrom a liquid to a solid body by the diminution of temperature,is very numerous. Kot only water when converted into ice un-dergoes such an expansion, but all bodies w hich by cooling as-sume the form of crystals. The prodigious force with which waterexpands in the act ot freezing has been long known to philosophers.Class bottles Idled with water are commonly broken in pieces whenthe water freezes. The Florentine academicians burst a brass globewhose cavity was an inch in diameter, by tilling it w ith water andfreezing it. The force necessary for this effect was calculated byMuscheubroek at 27720 lbs. But the most complete set of ex-periments on the expansive force of freezing water are those madeby major Williams at Quebec,and published in the second volumeot the Edinburgh Transactions. This expansion has been ex-plained, by supposing it the consequence of a tendency whichwater, in consolidating, is observed to have to arrange its particlesin one determinate manner, so as to form prismatic crystals, cross-ing each other at angles of 60’ and 120°. The force with whichthey arrange themselves in this manner must be enormous, since itenables small quantities of water to overcome so great mechanicalpressures. Various methods have been tried to ascertain the spcci-Jic gravity of ice at 32°; that which succeeded best was to dilutespirits of wine with water till a mass of solid ice put into it remainedin any part of the liquid without either sinking or risum. Thespecific gravity of such a liquid is 0.1)2, which of course isllie spe-cific gravity of ice, supposing the specific gravity of water at (10°to be 1. This is an expunsson much greater than water experienceseven when healed to 212°. We see from this, that water, whenconverted into ice, no longer observes that equable expansionmeasured by Mr. Dalton, but undergoes a very rapid and con-siderable augmentation of bulk. The very same expansion is ob-served during the crystallization of most of the salts ; all of themat least w hich shoot into prismatic forms. Hence the reason thatthe glass vessels in which such liquids are left, usually break topieces when the crystals are formed. This expansion of these«i. T* cannot be considered as an exception to the general fact,nat bodies increase in bulk when beat is added to them; for the•expansion is the consequence, not of the diminution of heat, but ofthe change in their state from liquids to solids, and the new arrango-inent of their particles which accompanies or constitutes that change,f t must be observed, how ever, that ail bodies do not expand whenthey become solid. There are a considerable number which di-mmish in hulk ; and in these the rate of diminution in most casesis rather increased by solidification. When liquid bodies are con-verted into solids, they either form prismatic crystals, or they farma mass in which no regularity of arrangement can be perceived. Inme first case, expansion accompanies solidification ; in the secondffiace, contraction accompanies it. Water and all the salts furnish,instances of the first, and tallow and oils are examples of the second.In these last bodies the solidification dees not take place instautane-? us *>» as in water and salts, but slowly and gradually : they first’f'conie viscid, and at last quite solid. Most of the oils, when' theysolidify, form very regular spheres. The same thing happens t'onwr’ to sonie nietals. It has been thought that all combus-]'i 'T'hls contract, when they become solid, while incombusti-I mpfids expand ; but there are excq.'ticms lb this rule. Sul-p nine acid does not by congelation alter its appearance; but castperhaps sulphur also, expand in the act of congealing.

FXPARlIi, a term'- -in the court of chancery, when aonnvussion is taken oi executed by one side or party only,

P'jn the other par' .eglecling or refusing to join therein. Whenotfi the parties proceed together, it is called a joint commission.

1 ' x " a Rte I alis, a writ that lies for a bailiff or receiver, thatA" auditors assigned to pass his accounts, cannot procure from|i e "’ ri ”'sonabie allowance, but is cast into prison ; in which case^I’-cffice is to sue Ibis writ out of the chancery, directed to the'-'nil to take the lour mainpernors to bring his body before the

barons of the exchequer, on a certain day, and to warn the lord toappear at the same time.

EXPECTANCY, ESTATES IN, are of two sorts; one cre-ated by act of the parties, called a remainder; the other, by act oflaw, called a reversion.

EXPECTANT, in law signifies having relation to, or depend-ing on: thus, where land is given to a man and his wife, and totheir heirs, they have a fee simple estate ; but if it be given to themand the heirs of their bodies begotten, they have an estate tail, anda fee expec tant, which is opposed to fee simple.

EXPECTATION, in the doctrine of chances, is applied toany contingent event, and is capable of being reduced to the rulesof computation. Thus a sum of money in expectation, when aparticular event happens, has a determinate value before that eventhappens ; so that if a person is to receive any sum, e. gr. 101. whenan event takes place, which lias an equal probability of happeningand failing, the value of the expectation is half that sum, or 51. andin all cases the expectation of obtaining any sum is estimated, bymultiplying the value of the Sum expected by the fraction which re-presents the probability of obtaining it. The expectation of a per-son who has three chances in five ot obtaining 1001. is equal to -j. x100 or O'OI. and the probability of obtaining 1001. in this care isequal to See Chances.

Expectation of Life. See Annuities.

EXPECTORANTS, in pharmacy, medicines which promoteexpectoration; such as squills, &c.

EXPECTORATION, the act of evacuating orbiingingupphlegm, or other matters out of the trachea, lungs, &c. by cough-ing, hanking, spitting, fkc.

EXPEDlTATION, in the forest laws, signifies the cutting out.of the halls of a dog’s fore-feet for the preservation of the king’-game. Every one living near the park, that keeps any great don notexpeditated forfeits 3s. 4d. to the king. I n mastiffs, not the ballof the feet, but the three claws are to be cut to the skin.

EXPERIMENT, in philosophy, is the trial of the result oreffect of the applications and motions of natural bodies, in order f«discover some of their motions and relations, whereby to ascertainsome of their phenomena or causes.

EXPERIMENTAL PHILOSOPHY, that philosophy whichproceeds on experiments, which deduces the laws of nature, andthe properties and powers of bodies, aild their actions upon eachother, from sensible'experiments and observations. The businessof experimental philosophy is to inquire into and to investigate thereasons and causes of the various appearances or pha'nOmena ofnature, and to make the truth or probability thereof obvious andevident to the senses, by plain, undeniable, and adequate experi-ments, representing the several parts of the grand machinery andagency of nature. In our enquiries into nature, we are to be con-ducted by those rules and maxims which are found to be genuine,and consonant t'o a just method'of physical reasoning; and theserules of philosophizing are by the greatest 1 master in science, sirIsaac Newton , reckoned fbur, which ate as follows: 1. Morecauses of natural things are not to be admitted, than are both true,and sufficient to explain the phicnomcna; for nature does nothingin vain; but is simple, aild delights not in superfluous Causes'ofthings. 2. And, therefore, of natural effects of the same kind, thesame causes are to be assigned, as far as'it can be done: aS'dfrespiration in mafi and beasts, of the descent of stones in Europe ami America , of light in a culinary fire and iHthe'svtn, and of thereflection of light in the earth" and in the planets. 3. The qualitiesof natural bodies which cannot be increased or diminished, aridagree to all bodies in which experiment^ can be made, art' to bereckoned as the qualities of all bodies whatsoever: thus, becauseextension, divisibility, hardness, impenetKibility, mobility, the visinertisc, and gravity, are loiind in ail bodies' which fall ifirdarour cognizance or inspection, v.e may justly conclude they be-long to all bodies whatsoever, and art therefore tube esteemitithe original and universal properties of all natural'bodies. 4.In Experimental philosophy, propositions collected from theihamomena by induction are deemed (notwithstanding contrarylypofhcb'cs) cither exactly or vary nearly true, till other pheno-mena occur, by which they may be rendered either more accu-rate, or liable to exception. This ought to be done, lest argu-ments of induction should be destroyed by' hypotheses. These fourrules of philosophising, arc premised by sir Isaac Newton to his

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