CONTENTS 



CHAPTER IV 



THE DEVELOPMENT OP THE TELEPHONE 



Early experiments of Hauksbee, p. 67 An early conception of the 

 telephone, p. 68 Wheatstone's "magic lyre telephone," p. 69 

 Bourseul suggests an electrical telephone, p. 71 An interesting 

 coincidence, p. 73 Dr. Graham Bell describes his invention, p. 

 74 His studies of Helmholtz's experiments, p. 75 Different kinds 

 of currents, p. 77 A human ear used in the experiments, p. 79 

 Bell versus Gray, p. 81 Practical improvements, p. 83 Telephone 

 equipment, p. 85 Telephone exchanges, p. 86 Automatic tele- 

 phone systems, p. 87 The wireless telephone, p. 88 Instruments 

 of Dr. DeForest, p. 90 Working of the wireless telephone ex- 

 plained, p. 91. 



CHAPTER V 



THE EDISON PHONOGRAPH 



Edison's early patents, p. 93 The phonograph of 1877, p. 94 

 Clockwork and electricity for rotating the cylinder, p. 95 How the 

 sounds are recorded on the wax cylinder, p. 96. 



CHAPTER VI 



PRIMITIVE BOOKS 



Assyrian and Egyptian books, p. 99 Terra-cotta books of the 

 Babylonians and Assyrians, p. 102 The palm-leaf books of the 

 Hindus, p. 106 Folded books, p. 107 The text of ancient books, 

 p. 112. 



CHAPTER VII 



THE PRINTING /ND MAKING OF MODERN BOOKS 



The invention of printing in the West, p. 120 Gutenberg's press, 

 p. 121 The cylinder press invented, p. 123 Napier's press, p. 124 

 The Hoe cylinder press invented, p. 125 The advent of the 

 "type-revolving machine," p. 126 The press invented by Richard 

 M. Hoe, p. 127 Method of casting stereotype plates invented, p. 

 128 The introduction of "web" presses, p. 129 A modern news- 

 paper press, p. 131 Speed of the perfecting press, p. 133 A per- 

 fected magazine press, p. 135 Color-printing on rotary presses, 

 P- 138 Other aids to the printer, p. 139 Type-setting machines, 

 p. 141 The Mergenthaler linotype, p. 142 The Lanston mono- 



[iv] 



