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 Electric Needle Telegraph, invented in 1837.

Wheatstone’s Electric Needle Telegraph, invented in 1837.

The American Electro Magnetic Telegraph / With the Reports of Congress, and a Description of All Telegraphs Known, Employing Electricity or Galvanism · Alfred Vail · 第 13 / 16 章