CHAPTER XXVII.
Electricity is a property of force which resides in all matter, and which constantly seeks to establish an equilibrium.
562. Why is it called electricity?
Because it first revealed itself to human observation through a substance called, in the Greek language, electrum. This substance is known to us as amber.
563. In what way did electrum induce attention to this property of force in matter?
Thales, a Greek philosopher, observed that, by briskly rubbing electrum, it acquired the property of attracting light particles of matter, which moved towards the amber, and attached themselves to its surface, evidently under the influence of a force excited in the amber.
It is a resinous substance, hard, bitter, tasteless, and glossy. It has been variously supposed to be a vegetable gum, a fossil, and an animal product. It is probably formed by a species of ant that inhabit pine forests. The bodies of ants are frequently found in its substance.