I. Attraction

Attraction is the term employed to denote that power which causes bodies to approach towards each other, and which preserves them in a state of union after they come into contact. We are ignorant of the cause of this power, but some of the laws respecting it are sufficiently evident: and, from observing the different phenomena to which these give rise, we are inclined to believe that there are different species of attractions, although, perhaps, the difference is more in degree than in kind.

When this power is exerted on masses of matter, at sensible distances, in the direct ratio of the quantity of the matter, and the inverse ratio of the square of the distance, it is named Gravitation; but when its operation is confined to the minute atoms of bodies, and is exerted only when these are near to each other, or in apparent contact, it is denominated Contiguous Attraction. The former causes bodies on this globe to fall in a line perpendicular to its surface, preserves the planets in their orbits, and sustains in their places all the parts of the magnificent frame of the Universe: the second is the cause of the regular figures of natural bodies, and of the various combinations of matter which take place in and upon the surface of our globe. It is this species which we are here to examine.

Contiguous attraction, operating on particles of the same kind, forms an aggregate or mass; and the power, in this instance, is named the attraction of aggregation, or cohesion; but, acting on dissimilar particles, and producing bodies possessed of new properties, different from those of their components, it constitutes chymical attraction, or affinity.