e instruc- Optical transmissions, however, have, over electrical to communicate with each other from great distances, ones, an advantage that in certain cases must make tion of operators, and it became necessary to abandon and the first telegraphs were probably based upon op- them prevail, and that… … vessels communicate with and a longer one to a dash. Fig. l.-MILITARY OPTICAL TELEGRAPH WITH HELI0STAT The apparatus now used each other and with ports by are of Col. Mangin's inven- means of flags by day and of other material connection between the two stations. tion. There are two kinds of them,…
Patented · Munn · Valve · Center · Water · Patents · Scientific American · Luminous · Galvanized iron · Steam engine · Ship railway · Address munn · Novel construction · Lever bar · Sewing machine · Cast Iron · Side bars
Internet Archive · Public domain (published before 1931). Free to use for anything.
