ELECTROSTATICS, that branch of elec trical science dealing with electricity at rest, or static; opposed to electrodynamics, which deals with electricity as a force, in action. In the period of early research the electrical phe nomena produced by friction came to be called static electricity, and it has been convenient to retain the nomenclature, although it is recog nized that all divisional names of electricity are arbitrary, for in all of them we deal with the same unknown thing whose phenomena we ob serve largely through its high vibrations. The terms free electricity and atmospheric electricity (q.v.). were formerly much used to describe the electricity which we recognize as resident in the air and clouds above us; but to-day the term static electricity is the one most commonly employed to describe that drawn from the at mosphere on a kite-string; or that which ac cumulates in a pile of printing paper which has been subjected to some frictional contact that causes the sheets to adhere to each other; or to electrification in a driving belt caused by some accidental rubbing in the course of • its travel.
The first discoveries regarding electricity were regarding its static qualities. In the handling of amber, which is a fossilized vege table resin, it was found to display peculiar phenomena when rubbed, attracting light par ticles of matter. This phenomena came to be called electric, after Greek elektron, the name for amber. Later glass was found to display similar yet opposite phenomena on being rubbed, and there arose the terms and ous)) electricity, for the sort produced by rub bing glass or amber respectively, and which have since been identified as simply positive and negative electricity. It was also learned that there is always a balance maintained be tween positive and negative electricity, and that the development of a given amount of one means an equivalent amount of the other. For a fuller description of the development of knowledge regarding frictional electricity which we now call static electricity, see the article on