CONTENTS. XI 



Page 



57. Wheatstone's Universal Telegraph 82 



58. Simple Morse Circuit 84 



69. Morse Eecorders 85 



60. Siemens' (Morse) Embossing Instrument, with Movable 



Magnet 86 



61. The Morse Alphabetical Code 87 



62. ,, Transmitting Plate 90 



63. ' ,, Apparatus with Eelay 92 



64. Simple Morse Embosser for Two Stations with Eelay . . 93 



65. Intermediate Station Commutators 95 



66. Nottebohm's Commutator 96 



67. Siemens and Halske's Commutator 98 



68. Borggreve's 100 



69. Commutator for Stations with Three or Pour Lines . . . 102 



70. Battery Commutator 104 



71. Translation . . . ., 104 



72. Yarley's Apparatus for Translation 107 



73. Static Induction in Submarine Lines Ill 



74. Siemens' Submarine Key 113 



75. De Sauty's 115 



76. Varley's Switch for Submarine Work 117 



77. John's Ink-printing (Morse) Apparatus 120 



78. Digney's Ink-Eecorders 122 



79. Direct Working Ink- Writers of Siemens and Halske . . 125 



80. Arrangement of a Board with the Direct-working Ink- 



Writer 127 



81. Morse Telegraph worked by Induction Currents . . . 131 



82. Polarized Eelay 132 



83. Plan of Connections 1 34 



84. The Magneto -Induction Key 136 



85. Siemens' Polarized Ink Eecorder 138 



86. ,, ,, ,, used as a Submarine Koy 139 



87. Complete Submarine Board 142 



88. The Sounder 146 



89. Burning Holes in Eecording-paper ........ 147 



90. Morse Apparatus, worked by Closed Circuit . . . . . 148 



91. Telegraphing in Opposite Directions in the same Line . . 154 



92. Gintl's Method by Electro -Magnetism . . . V V . . i54 



93. ,, ,, Chemical Telegraph . . .' ; . v '. . . 156 



94. Frischen and Siemens' Method 158 



95. Telegraphing in the Same Direction in the Same Line . . 160 



96. Automatic Printing Telegraph 163 



97. Siemens' Magneto -Electric Type Telegraph 166 



93. Stoehrer's Double Style Telegraph 172 



