adopted Alexander Graham Bell American Bell Telephone annunciator apparatus application filed armature automatic Bell Company Bell Telephone Company Bell's Boston cable carbon central office Chapter committee common battery system communication conductor connected construction described diaphragm district Edison effect Electric Telegraph Electrical Engineers electro-magnet Exchange Association Report exchange system experience gutta-percha illustrated indicator induction coil instrument insulation invention London magnet manufacture ment metallic circuit method miles multiple switchboard National Telephone Exchange number of subscribers obtained Oliver Heaviside operator paper patent pipe placed plug pole Post Office practical private branch exchange purpose receiver recognised reed Reis relay resistance Scribner signal sound Speaking Telephone speech spring jack station subscriber's switch tele Telegraph Company Telegraph Engineers Telephone Exchange Association tion transmission transmitter trunk tube U.S. specification underground United vibration Visible Speech Western Electric Company Western Union Wheatstone whilst wire York
Page 202 - For you must not suppose, because I am a man of letters, that I never tried to earn an honest living. I began trying to commit that sin against my nature when I was fifteen, and persevered, from youthful timidity and diffidence, until I was twentythree.
Page 90 - ... could be connected as desired, establishing direct communication between any two places in the city. Such a plan as this, though impracticable at the present moment, will, I firmly believe, be the outcome of the introduction of the telephone to the public.
Page 100 - Electrical undulations may also be caused by alternately increasing and diminishing the resistance of the circuit, or by alternately increasing and diminishing the power of the battery.
Page 26 - The more I reflected upon this arrangement the more feasible did it seem to me ; indeed, I saw no reason why the depression of a number of keys at the...
Page 60 - One of the ways in which the armature c, Fig. 5, may be set in vibration has been stated above to be by wind. Another mode is shown in Fig. 7, whereby motion can be imparted to the armature by the human voice or by means of a musical instrument.
Page 53 - This second electro-magnet has a solid bar of iron for core, which is connected at one end, by a thick disc of iron, to an iron tube surrounding the coil and bar. The free circular end of the tube constitutes one pole of the electro-magnet, and the adjacent free end of the bar-core the other.
Page 100 - The reciprocal vibration of the elements of a battery, therefore, occasions an undulatory action in the voltaic current. The external resistance may also be varied. For instance, let mercury or some other liquid form part of a voltaic circuit, then the more deeply the conducting-wire is immersed in the mercury or other liquid, the less resistance does the liquid offer to the passage of the current. Hence, the vibration of the conducting-wire in mercury or other liquid included in the circuit occasions...
Page 24 - I took coach, having first discoursed with Mr. Hooke a little, whom we met in the streete, about the nature of sounds, and he did make me understand the nature of musicall sounds made by strings, mighty prettily; and told me that having come to a certain number of vibrations proper to make any tone, he is able to tell how many strokes a fly makes with her wings (those flies that hum in their flying) by the note that it answers to in musique during their flying.
Page 29 - Without going into details, I shall merely say that the great defects of this plan of multiple telegraphy were found to consist, firstly, in the fact that the receiving operators were required to possess a good musical ear in order to discriminate the signals ; and secondly, that the signals could only pass in one direction along the line (so that two wires would be necessary in order to complete communication in both direcTHE SPEAKING TELEPHONE. tions). The first objection was got over by employing...
Page 67 - The instruments will be kept in good working order by the lessors, free of expense, except from injuries resulting from great carelessness. Several Telephones can be placed on the same line at an additional rental of $10 for each instrument; but the use of more than two on the same line where privacy is required is not advised. Any person within ordinary hearing distance can hear the voice calling through the Telephone.