Logo
Prev
Bookmark
Rotate
Print
Next
Contents
All Pages
Related Articles
Browse Issues
Help
Search
Home
'
National Geographic : 1947 Mar
Contents
U naionai ueuograpmic Ducity Ektachrome by Willard R.Culver Man-made Crystals, Better in Some Ways than Natural Quartz, Are "Grown" in Chemical Tanks for Telephone Use Crystals are grown by rotating "seeds" (Plate XIII) in a chemical solution. Chemicals deposited on the seeds buildthem up todesired size. Because plates cut from crystals vibrate at precise frequencies, they are used to filter out single conversations from the many thattravel together over telephone lines.
Links
Archive
1947 Apr
1947 Feb
Navigation
Previous Page
Next Page
