Chicago : [Popular Engineering Pub. Co.] · leaf 188
neral or crystal type of detector. materials phosphor bronze is the best for The active material used in this detector this purpose. The screw (G) has an 8-32 is iron pyrites, or "fool's gold," as it is some- thread, and a lock nut as shown. The ver- times called. This is a sulphide of iron, tical… … CONSTRUCTION OF THE "PYRON DETECTOR it is revolved. (W) is a metal washer. (J) large quantities, both in the massive con- should be soldered into the standard (A). dition, and in bright cubical crystals. Either It will be found that the iron pyrites has a fragment or a crystal will serve our pur- a…
Electricity
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