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 / REPORTS TO CONGRESS ON THE SUBJECT OF ELECTRO MAGNETIC TELEGRAPHS.

REPORTS TO CONGRESS ON THE SUBJECT OF ELECTRO MAGNETIC TELEGRAPHS.

The American Electro Magnetic Telegraph / With the Reports of Congress, and a Description of All Telegraphs Known, Employing Electricity or Galvanism · Alfred Vail · 第 8 / 16 章