a great law-officer under the king, whose duty it is to exhibit informations, and prosecute for the crown, in matters criminal, and to file bills in the exchequer for anything concerning the king in inheritance or profits.

**Attraction.**

The word Attraction is used to denote what we observe when one body approaches another, or tends to approach it, without any apparent impulse or other cause to which the motion can be ascribed.

We have instances of attraction when iron approaches the magnet, when certain bodies are placed near an excited electric, and when a stone falls to the earth. We say likewise that the earth attracts the moon; by this mode of expression meaning no more than that the moon is continually deflected towards the earth, from the rectilineal course which it would otherwise pursue. It is likewise in this sense that we must be understood when we say that the sun attracts all the planets.

In the instances already mentioned, attraction extends to a distance. In other cases it is confined within limits so extremely narrow as to become imperceptible at an interval which cannot be appreciated by the senses. Of this kind is the attraction which takes place between the particles of the same fluid, as is apparent from the round figure of small drops. To this class likewise belongs the attraction between fluid and solid bodies; whence originate the very interesting appearances observed in capillary tubes, and other kindred phenomena. An attraction between the small elementary particles of all solid bodies is manifest from the force with which they cohere or resist an endeavour to separate them. In many cases the intensity of this force is prodigiously great in contact or at the nearest distances; while it ceases to act upon making the smallest separation between the parts. Lastly, chemistry develops innumerable instances of attraction between the molecules of the bodies about which it is conversant; insomuch that it is to this principle, under the name of affinity, that we must ultimately ascribe the various decompositions and new combinations which occur in that science.

All these phenomena, although very different from one another in other respects, have yet this in common, that we observe in certain bodies a tendency to approach one another, and to resist a separation, with some degree of force. The facts are certain, and are attended with no ambiguity; and it is to express these facts that the term attraction is used in physics.

We likewise observe, in some bodies, a tendency to fly off from one another when they are brought near. This is called repulsion.

The word force has, in general, some degree of obscurity. It is used to denote the cause of motion; but we have no direct knowledge of it, and we judge of its intensity by the effect which we suppose it to produce. In all our reasoning concerning forces, it is the changes of motion which we measure and compare together, and which are really the subjects of our thoughts. Attraction and repulsion are forces or principles of motion, known to us only by the phenomena we observe; but the circumstance of their implying action at a distance is an additional source of obscurity in which other kinds of force do not participate.

It certainly is inconceivable that motion should be produced at a distance, when no connection can be traced between the body moved and that which is supposed to produce the motion. We are strongly impressed with the prejudice, that a body cannot act but where it is; and we find difficulty in admitting that the mere presence of two bodies, without the intervention of any mechanical means, can be a satisfactory cause of motion. On this account attraction has been classed by some with the occult qualities of the schools; and the favourers of this doctrine have been reproached with reviving exploded notions in philosophy. Impulse is a principle of motion more familiar to us, and to which we are not disposed to make equal objection. Whenever the communication of motion can be traced to this source, we are satisfied that the effect is justly explained. Hence many philosophers have been of opinion, that impulse is the only cause of motion that can