developed a cat’s-whisker detector using carborundum,
and Greenleaf Whittier Pickard developed
a cat’s-whisker detector using galena.
Cat’s-whisker detector
Different crystals made cat’s-whisker detectors—silicon,
carborundum, galena, molybdenite, iron pyrite, iron disulfide.
Some galena crystals made good detectors,
and some didn’t no matter how you adjusted them.
Generally, the magic wasn’t in the type of crystal;
it was in finding the right pressure and point of contact.
The fine point of the wire had to touch the crystal gently
and some positions on the crystal wouldn’t work at all.
Crystal divination
The power of crystals
to orient the mind
precedes discovery
of its electromagnetic effects.
Listen carefully
to the inside a seashell.
It does indeed seem
like the sound of the sea.
I made a radio in high school with a germanium crystal diode,
and, using our garage door as an antenna,
listened to the local AM station with an ear-bud.
I made a radio in high school with a germanium crystal diode, and, using our garage door as an antenna, listened to the local AM station with an ear-bud.
See also in The book of science:
Readings on wikipedia: