I have showed above, chap.
4, that we get the idea of space, both by our sight and touch; which, I think, is so evident, that it would be as needless to go to prove that men perceive, by their sight, a distance between bodies of different colours, or between the parts of the same body, as that they see colours themselves: nor is it less obvious, that they can do so in the dark by feeling and touch.
3.

Space and Extension.
This space, considered barely in length between any two beings, without considering anything else between them, is called DISTANCE: if considered in length, breadth, and thickness, I think it may be called CAPACITY.

When considered between the extremities of matter, which fills the capacity of space with something solid, tangible, and moveable, it is properly called EXTENSION.

And so extension is an idea belonging to body only; but space may, as is evident, be considered without it.

At lest I think it most intelligible, and the best way to avoid confusion, if we use the word extension for an affection of matter or the distance of the extremities of particular solid bodies; and space in the more general signification, for distance, with or without solid matter possessing it.
4.