ATT 



AUC 



parts of bodies adhere together, it is most 

 probable, by the attraction of cohesion, 

 (as do also their combinations into crys- 

 tals and other forms,) modified in some 

 degree by that attraction caused by elec- 

 tric fire. 



The attraction which takes place among 

 substances in solution is not so easily 

 comprehended, as we know nothing as 

 yet of the exact state in which a sub- 

 stance capable of solidity exists, when 

 dissolved in a fluid. In our present state 

 of knowledge, we can only consider it as 

 a fluid itself, capable of reassuming a so- 

 lid form in certain circumstances. 



The attraction which takes place be- 

 tween bodies in a state of vapour is simi- 

 lar to that in a fluid state ; their precise 

 and minute state in that condition is un- 

 known ; but the combinations which en- 

 sue from the attractions of many, in both 

 states, are familiar to all chemists, and 

 from them have proceeded many of the 

 most useful substances which we possess. 

 It is very fortunate for us, however, that 

 if the knowledge of the minute and pri- 

 mary state of bodies is, as it were, con- 

 cealed from our view by an impenetrable 

 veil, it is not of any very great importance 

 to us, as the effects which bodies pro- 

 duce on each other can be known to us 

 without it, and it is this latter species of 

 knowledge that affords us the dominion 

 over nature, supplies our wants, andforms 

 the basis of worldly happiness. 



The characteristic marks of affinity 

 maybe reduced to the three following : 



1. It acts only at insensible distances, 

 and of course affects only the minute 

 parts of bodies. 



2. This force is always the same in the 

 same substances ; but is different in differ- 

 ent substances. 



3. This difference is considerably mo- 

 dified by the mass. Thus, though A has 

 a greater affinity for C than B has, if the 

 mass of B be considerably increased, 

 while that of A remains unchanged, B 

 becomes capable of taking a part of C 

 from A. 



ATTRIBUTES, in logic, are the predi- 

 cates of any subject, or what may be af- 

 firmed or denied of any thing. 



ATTRIBUTES, in painting and sculpture, 

 are symbols added to several figures, to 

 intimate their particular office and cha- 

 racter. 



Thus, the eagle is an attribute of Jupi- 

 ter ; a peacock, of Juno ; a caduce, of 

 Mercury ; a club, of Hercules ; and a palm, 

 of Victory. 



ATTRITION, the rubbing or striking 

 VOL. II. 



of bodies one against another, so as to 

 throw off some of their superficial parti- 

 cles. 



The grinding or polishing of bod esis 

 performed by attrition, the effects of 

 which are, heat, light, fire, and electricity. 



ATTRITION, is also often used for the 

 friction of such simple bodies, as do not 

 wear from rubbing- against one another, 

 but whose fluids are, by that motion, sub- 

 jected to some particular determination ; 

 as the various sensations of hunger, pain, 

 and pleasure, are said to be occasioned by 

 the attrition of the organs formed for 

 such impresssions. 



AVALANCHES, a name given in Swis- 

 serland and Savoy, to those prodigious 

 masses of snow which are precipitated, 

 witli a noise like thunder, and in large 

 torrents, from the mountains, and which 

 destroy every thing in their course, and 

 have sometimes overwhelmed even whole 

 villages. In 1719, an avalanche from a 

 neighbouring glacier overspread the 

 greater part of the houses and baths at 

 Leuk, and destroyed a considerable num- 

 ber of inhabitants. The best preserva- 

 tive against their effects being the fo- 

 rests, with which the Alps abound, there 

 is scarcely a village situated at the foot of 

 a mountain that is not sheltered by trees, 

 which the inhabitants preserve with un- 

 common reverence. Thus, what consti- 

 tutes one of the principal beauties of the 

 country, affords also security to the peo- 

 ple. 



AVAST, in the sea language, a term 

 requiring to stop, to hold, or to stay. 



AUBLETIA, in botany, so named from 

 M. Aublet, the author of the history of 

 plants in Guiana, a genus of the Polyan- 

 dria Monogyma class and order. Essen- 

 tial character : calyx five-leaved ; corolla 

 five-petalled ; capsule many celled, echi- 

 nate, with many seeds in each cell. There 

 are four species, natives of Guiana. 



AUCTIONS, and AUCTIONEERS, every 

 person exercising the trade of an auc- 

 tioneer, within the bills of mortality, shall 

 pay 20*. fora licence; and without the 

 bills of mortality 5s. Auctions and auc- 

 tioneers are regulated by several statutes 

 during the present reign. A bidder at 

 an auction, under the usual conditions 

 that the highest bidder shall be ti:-e pur- 

 chaser, may retract his bidding any time 

 before the hammer is down. 



AUCUBA, a j^nas of the Monoecia 

 Tetrandria. Essential character: male 

 four-toothed ; corolla four-petalled ; ber- 

 ry one-seeded ; female nectary none ; nut 



N 



