首页 / 官方藏书 / The American Electro Magnetic Telegraph / With the Reports of Congress, and a Description of All Telegraphs Known, Employing Electricity or Galvanism / Wheatstone’s Rotating Disc Telegraph, invented, 1841.

Wheatstone’s Rotating Disc Telegraph, invented, 1841.

The American Electro Magnetic Telegraph / With the Reports of Congress, and a Description of All Telegraphs Known, Employing Electricity or Galvanism · Alfred Vail · 第 15 / 16 章