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action applied armature arrangement articulate sounds ascertained audible bar magnet battery Bell telephone Bell's carbon caused centimetres centre circuit communication connected consequently copper corresponding cylinder Daniell cell diaphragm distance distinctly duced Edison effects produced electric electric current electro-magnet Elisha Gray emit employed experiments fastened fixed galvanometer hear heard helix Hughes induced currents induction coil influence inserted instru instrument intensity invention Leclanche cell local battery magnetic core membrane ment mercury Messrs metallic microphone millimetres Morse mouth-piece movements musical necessary obtained ordinary telephone phonautograph phonograph phragms piece placed platinum poles Preece pressure react receiving telephone regulated represented in Fig reproduced resistance result Ruhmkorff coil screw sender sending sensitive soft iron sounds produced speak spring string telephones strument surface tele Telegraphic Journal telegraphic wire tin-foil tion transmission tuning-fork variations vibrating disk vibrating plate voice voltaic yards
Page 37 - In the Canadian department I heard 'To be or not to be, . . . there's the rub,' through an electric telegraph wire; but, scorning monosyllables, the electric articulation rose to higher flights, and gave me passages taken at random from the New York newspapers: — 'SS Cox has arrived' (I failed to make out the SS Cox) ; 'The City of New York...
Page 46 - While engaged in these experiments I was struck with the remarkable disproportion in weight between the membrane and the bones that were vibrated by it. It occurred to me that if a membrane as thin as tissue paper could control the vibration of bones that were, compared to it, of immense size and weight, why should not a larger and thicker membrane be able to vibrate a piece of iron in front of an electro-magnet, in which case the complication of steel rods shown in my first form of telephone, fig.
Page 48 - To my delight an answer was returned through the instrument itself, articulate sounds proceeded from the steel spring attached to the membrane, and I heard the sentence, 'Yes, I understand you perfectly." It is a mistake, however, to suppose that the articulation was by any means perfect, and expectancy no doubt had a great deal to do with my recognition of the sentence ; still, the articulation was there, and I recognised the fact that the indistinctness was entirely due to the imperfection of the...
Page 51 - ... way in which they from time to time placed before me the results of their discoveries entitles them to my warmest thanks and to my highest esteem. It was always my belief that a certain ratio would be found between the several parts of a telephone, and that the size of the instrument was immaterial ; but Professor Peirce was the first to demonstrate the extreme smallness of the magnets which might be employed.
Page 13 - We know that sounds are made by vibrations, and are made sensible to the ear by the same vibrations, which are reproduced by the intervening medium. But the intensity of the vibrations diminishes very rapidly with the distance; so that even with the aid of speaking tubes and trumpets, it is impossible to exceed somewhat narrow limits.
Page 54 - Ruhmkorff's coil when the primary circuit is made and broken with sufficient rapidity ; when two rheotomes of different pitch are caused simultaneously to open and close the primary circuit a double tone proceeds from the spark. A curious discovery, which may be of interest to you, has been made by Professor Blake. He constructed a telephone in which a rod of soft iron, about six feet in length, was used instead of a permanent magnet. A friend sang a continuous musical tone into the mouthpiece of...
Page 14 - Suppose that a man speaks near a movable disk, sufficiently flexible to lose none of the vibrations of the voice, that this disk alternately makes and breaks the currents from a battery : you may have at a distance another disk, which will simultaneously execute the same vibrations.
Page 279 - OCEAN. The Ocean, Atmosphere, and Life. Being the Second Series of a Descriptive History of the Life of the Globe.
Page 51 - A platinum wire attached to a stretched membrane completed a voltaic circuit by dipping into water. Upon speaking to the membrane, articulate sounds proceeded from the telephone in the distant room. The sounds produced by the telephone became louder when dilute sulphuric acid, or a saturated solution of salt, was substituted for the water. Audible effects were also produced by the vibration of plumbago in mercury, in a solution of bichromate of potash, in salt and water, in dilute sulphuric acid,...
Page 48 - I recognised the fact that the indistinctness was entirely due to the imperfection of the instrument. I will not trouble you by detailing the various stages through which the apparatus passed, but shall merely say that after a time I produced the form of instrument shown in fig. 25, which served very well as a receiving telephone. In this condition my invention was exhibited at the Centennial Exhibition in Philadelphia.