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may change his attorney without rule of court, whilst tire-suit isdepending: and attorneys are not generally obliged to deliver upthe writings in their hands, till their fees are satisfied ; likewise,an action does not lie against an attorney, for what he advises inthe way of his profession; yet if an attorney plead any plea, orappear, without warrant from Ids client, action of the case liesagainst him. Attorney's have the privilege to sue and be sued inthe courts of Westminster, where they practice ; and they shallnot be chosen into offices against their will, except the militia.

Attorney of the duchy of Lancaster is the second officer inthat court.

Attorney-General, is a great officer under the king, createdby letters patent, whose office it is to exhibit informations, andprosecute for the crown in criminal causes ; and to tile bills in theexchequer, for any thing concerning the king in inheritance orprolits. To him come warrants for making of grants, pardons,&c. his salary from the crown is 1000/. per annum.

ATTRACTION, in natural philosophy, a general term usedto denote the cause by which bodies tend towards each other, andcohere till separated by some other power. The principle ofattraction, in the Newtonian sense of it, seems to have been firstsurmised by Copernicus . “ As for gravity,” says he, “ I considerit as nothing more than a certain natural appetence (appetentia)that the Creator has impressed upon all the parts of matter, inorder to their uniting or coalescing into a globular form, fortheir better preservation; and it is probable that the same poweris also inherent in the sun and moon, and. planets, that thosebodies may constantly retain that round figure in which wc beholdthem.” (De Rev. Orb. Cad. lib. 1. c. 9.) And Kepler callsgravity a'corporeal and mutual affection between similar bodies,in order to their union; and says positively, that no bodies what-soever were absolutely light, only relatively so; and consequently,that all matter was subjected to the law' of gravitation. (Ast.Nov. Introd.) The first in this country who adopted the notionof attraction, was Dr. Gilbert, in his book De Magnate; andthe next was the celebrated Lord Bacon . (Nov. Organ, lib. ii.aph. 36. 43. 48. Sviv. cent. i. exp. 33.) In France it was re-ceived bv Fermat and Robcrval ; and in Italy by Galileo andBorelli. ’ Dr. Ilooke, however, was the person who conceivedthe most just and dear notions of the doctrine of gravitation ofany before Newton ; in his work calk'd “ An Attempt to provethe Motion of the Earth1674. lie observes that the hypo-thesis on which he explains the system of the world, is in manyrespects different from all others; and that it is founded on thefollowing principles: 1. That all the heavenly bodies have notonly an'attraction or gravitation towards their own centres, hutthat they mutually attract each other within the sphere of theiractivity. 2. That all bodies which have a simple or direct motion,continue to move in a right line, if some force operating without,incessantly, does not constrain them to describe a circle, anellipse, or some other more complicated curve. 3. That at-traction is so much the more powerful, as the attracting bodiesare nearer to each other. But the precise determination of thelaws and limits of the doctrine of attraction, was reserved for thegenius of Newton: in the year 1666, he first began to turn hisattention to tins subject, when, to avoid (lie plague, lie bad re-tired from London into the country ; but, on account of theincorrectness of the measures of the terrestrial meridian, madebefore this period, he was unable to bring his calculations on thesubject to perfection at first. Some ve.-.is afterwards his attentionwas again called to attraction by a letter of Dr. Hook’s ; andHeard, having about this time measured a degree of the earth, inFrance , with great exactness, lie employed this measure in iiiscalculations, instead of the one lie had before used, and found, bythat means ; hat the moon is retained in her orbit by the solepower of gravity, supposed to be reciprocally proportional lo thesquares of the distances. According to this law, he al o found,that the tine described by bodies in their descent is an ellipse, ofwhich the centre of the earth occupies cue of the foci; and con-siderin'* afterwaids, that the orbits of the planets are in likemanner eHipses, having the centre of the sun in one of their foci,he had the satisfaction to perceive, that the solution which he hadundertaken only from curiosity, was applicable to some of themost sublime objects in nature! These discoveries gave birth tohis celebrated work, w hich has justly immortalized his name, en-titled “ Philosophical ' Naturalis Prineipia Mathemulica.” Attrac-

tion may be divided into two kinds. 1. That which is apparent atsensible distances, such is the attraction of gravity, or' magnetismand of electricity. 2. That which is observed only at very small,or insensible distances, which is called affinity, chemical attrac-tion, or molecular attraction. Philosophers now generally con-clude that it is the same force in eviry case, contemplated underdifferent aspects, yet subject to the same laws. 'Pile attraction ofgravity, or gravitation, called also among mathematicians thecentripetal force, is one of the most universal principles in nature.We see and feel it operate on bodies near the earth, and find byobservation, that the same power also obtains in the moon, andthe oilier planets primary and secondary, as well as in the comets;and even that this is the very power whereby they are all re-tained in their orbits, &c. Hence, as gravity is found in all thehollies which come under our observation, it is inferred, that itobtains in all others: and as it is found to be proportioned to thequantity of matter in eaeli body, it must be in every particlethereof; and hence every particle in nature is proved to attractevery other particle, &c. For the application of this principle tothe celestial motions, see Astronomy . Also this force is foundto be inversely .as the square of the distance. See Astronomyand Mechanics. By this heavy bodies descend, awl lightones ascend; projectiles are directed, vapours' awl exhalationsrise, and rains, &c. fall. By this rivers glide, the air presses, theocean swells, Sec. In ellect, the motions arising from this prin-ciple make the subject of that extensive branch of mathematics,called mechanics, or statics, with the parts or appendages thereof,hydrostatics, pneumatics, &c. Electrical Attraction, is that pro-duced by electrified bodies, and Magnelical Attraction is that oc-casioned!))' the influence of the magnet. Coulomb had shewnthat both these vary inversely as the square of the distance ; theyappear to depend on the motion of'some fluid or fluids, whichmotion, upon examination, may be found to depend on thegeneral principle of attraction. /Molecular or Chemical Attrac-tion, the force by which the minute particles, or molecular ofbodies mutually attract each other, when the distance betweenthem becomes insensible. '['Ids was formerly called affinity anddistinguished into many species, as affinity of aggregation, com-position, dissolution, precipitation, simple affinity, double affinity,reciprocal affinity, hygrometric affinity, Ac. See. But all theseare comprised in these three, simple attraction, elective attraction,complex attraction. Simple Attraction is when two substances,simple or compound, act on each other, to that the several partsof cadi act only by a collective force. When the two substancesare alike it is called aggregation or cohesion. When they are ofdifferent kinds, the union produces several variations in the at-tractive force. Elective Attraction is when two substances areacted upon by a third which has a stronger attraction to one of theconstituents than they have for one another. Thus, if to a solutionof silver in aqua fortis, mercury he added, the aqua forlis will beattracted by the mercury, and the silver will be precipitated, awlhence a new compound of quicksilver and aqua fortis is formed ;if again copper he added, it will assume the place of the quick-silver ; and if to this solution of copper a bright piece ot ironbe introduced, the acid will immediately quit the copper, andseize upon the iron, a quantity of which being dissolved in thefluid, the copper will In' deposited in its place on the surfai eof the bar of iron. The iron may afterwards be displaced by theaddition of an alkali. Complex Attraction, has place when acompound substance is decomposed by the attractions of twoother substances in union, one of them not being sufficient aloneto effect the decomposition as in elective attraction. We needhardly say how unjust it is in the generality of foreign philoso-phers to declare against a principle which furnishes so beautifula view, for no other reason but because they cannot conceive howone body should act on another at a distance. Indeed philosophyallows of no action but what is by immediate contact and im-pulsion ; for how can a body exert any active power where itdoes not exist? Yet we see effects without perceiving any suchimpulse ; and where there are eflbcts, we infer there are causes,whether we see them or not. But we may consider such effect 1 *without entering into the consideration of the causes, as indeedit seems the business of a philosopher to do ; lor to exclude anumber of pha-nomena which wc do see, will be to leave a greatchasm in the History of nature ; and to argue about actions whichwe do not see, will be to build castles in the air. It follows,

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