SPACE, is defined by Mr. Locke to be a simple idea, which we attain both by our sight and touch; the modes whereof are distance, capacity, extension, duration, &c. Space,considered barely in length between two bodies, is the same idea which we have of distance. If it be considered in length, breadth and thickness, it is pro perly called capacity ; when considered between the extremities of matter, which fills the capacity of space with something solid, tangible, and moveable, it is then called extension, so that extension is an idea belonging to a body, but space, it is plain, may be conceived without it. Each different distance is a different modifica tion of space, and each idea of any differ ent space is a simple mode of this such are, an inch, foot, yard, &c. which are the ideas of certain stated lengths, which men settle in their minds for the use, and by the custom of measuring. When these ideas are made familiar to men's thoughts, they can repeat them as often as they will, without joining to them the idea of the body, and frame to them selves the ideas of feet, yards, or fathoms, beyond the utmost bounds of all bodies; and by adding these still one to another, enlarge their idea of space as much as they please. From this power of repeat ing any idea of distance without ever com ing to an end, we come by the idea of im mensity. Another modification of space is taken from the relation of the termina tion of the parts of extension, or circum scribed space, amongst themselves; and this is what we call figure. Thisthe touch discovers in sensible bodies, whose ex tremities come within our reach ; and the eye takes both from bodies and colours, whose boundaries are within its view; where, observing how the extremities ter minate, either in straight lines, which meet at discernible angles, or in crooked ones, wherein no angles can be perceived, by considering these as they relate to one another in all parts of the extremities of any body or space, it has that idea we call figure, which affords to the mind infinite variety. Another mode belonging to this
head is that of place. There is another mode of space, the idea of which we get from the fleeting and perpetually perish ing partsof succession, which we call du ration. Space is usually divided into ab solute and relative. Absolute space is that considered in its own nature, with out regard to any thing external, which always remains the same, and is infinite and immoveable. Relative space, is that moveable dimension, or measure of the former, which our senses define by its po sitions to bodies within it, and this is the vulgar use for immoveable space. Relative space, in magnitude and figure, is always the same with absolute ; but it is not ne cessary it should be so numerically ; as if you suppose a ship to be, indeed, in abso lute rest, then the places of all things within her will be the same, absolutely and relatively, and nothing will change its place : but suppose the ship under sail, or in motion, and she will continually puss through new parts of absolute space ; but all things on board, considered relatively in respect to the ship, may be, notwith standing, in the same places, or have the same situation and position in regard to one another.
Sracz, in geometry, denotes the area of any figure, or that which fills the inter valor distance between the fines that ter minate it.