Glass

A fused mixture of silicates of various oxides. It is of extremely varied composition and its electric constants vary greatly. Many determinations of its specific resistance have been made. For flint gla at 100° C. (212° F.) about (2.06E14) ohms --at 60° C (140° F.) (1.020E15) (Thomas Gray) is given, while another observer (Beetz) gives for gla at ordinary temperatures an immeasurably high resistance. It is therefore a non-conductor of very high order if dry. As a dielectric the specific inductive capacity of different samples of flint gla is given as 6.57--6.85--7.4--10.1 (Hopkins on), thus exceeding all other ordinary dielectrics. The densest gla , other things being equal, has the highest specific inductive capacity.