ina&ivity of Matter, &c. hi

cohesion, in distinction to the attraction of gra-vitation : and it is the cause that in different de-grees of propinquity and contact, the parts ofmatter cleave together with such different de-grees of force, as to constitute all the differentdegrees of solidity and compactness, of fluidi-fy and brittlenefs, observable in bodies (s).

X. This attractive power must be conceiv-

vim quamcunque qua duo corpora ad se invicem tendunt ;licet forte illudper tmpulsum fiat. Cap. 5. de cohæiionepartium: Def. 4.

(s) Mr. Worcester , in his account of the principles ofnatural philosophy, after he hath pretty largely treatedof the attraction of cohesion, adds, p. 22. Having prov-ed the reality of this attrattion, it is no difficult matterto Jhew farther , that such a power is sufficient to explainhow the parts of bodies may flick together with as manydifferent degrees of cohesion as have been observed in nature.Therefore by the first philosophical rule, this attrattionought to be esteemed the true cause of cohesion of parts ; andfor that reason it is called the attraction of cohesion. Par-ticles of matter whose weight is greater than their attrac-tion, can produce only an incoherent mass like a heap of sand.Particles of matter whose attradlion is but very little great-er than their weight, snail conjlitute a fiuid. Particlesof matter whose attraction is very much greater than theirweight, shall form a compaSl and solid body. If the at-iraStion exceeds the weight in a moderate degree, theywill comfofe a soft body,