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e； and sentences which were unexpected could not be understood。 Clearly； if the phonograph were to become a practical instrument； it required to be much improved。 Nevertheless this apparatus sufficiently demonstrated the feasibility of storing up and reproducing speech； music； and other sounds。 Numbers of them were made； and exhibited to admiring audiences； by license； and never failed to elicit both amusement and applause。 To show how striking were its effects； and how surprising； even to scientific men； it may be mentioned that a certain learned SAVANT； on hearing it at a SEANCE of the Academie des Sciences； Paris； protested that it was a fraud； a piece of trickery or ventriloquism； and would not be convinced。
After 1878 Edison became too much engaged with the development of the electric light to give much attention to the phonograph； which； however； was not entirely overlooked。 His laboratory at Menlo Park； New Jersey； where the original experiments were made； was turned into a factory for making electric light machinery； and Edison removed to New York until his new laboratory at Orange； New Jersey； was completed。 Of late he has occupied the latter premises； and improved the phonograph so far that it is now a serviceable instrument。 In one of his 1878 patents； the use of wax to take the records in place of tinfoil is indicated； and it is chiefly to the adoption of this material that the success of the 'perfected phonograph' is due。 Wax is also employed in the 'graphophone' of Mr。 Tainter and Professor Bell； which is merely a phonograph under another name。 Numerous experiments have been made by Edison to find the bees…wax which is best adapted to receive the record； and he has recently discovered a new material or mixture which is stated to yield better results than white wax。
The wax is moulded into the form of a tube or hollow cylinder； usually 4 1/4 inches long by 2 inches in diameter； and 1/8 inch thick。 Such a size is capable of taking a thousand words on its surface along a delicate spiral trace； and by paring off one record after another can be used fifteen times。 There are a hundred or more lines of the trace in the width of an inch； and they are hardly visible to the naked eye。 Only with a magnifying glass can the undulations caused by the vibrating stylus be distinguished。 This tube of wax is filed upon a metal barrel like a sleeve； and the barrel； which forms part of a horizontal spindle； is rotated by means of a silent electro…motor； controlled by a very sensitive governor。 A motion of translation is also given to the barrel as it revolves； so that the marking stylus held over it describes a spiral path upon its surface。 In front of the wax two small metal tympanums are supported； each carrying a fine needle point or stylus on its under centre。 One of these is the recording diaphragm； which prints the sounds in the first place； the other is the reproducing diaphragm； which emits the sounds recorded on the wax。 They are used； one at a time； as the machine is required； to take down or to render back a phonographic message。
The recording tympanum； which is about the size of a crown…piece； is fitted with a mouthpiece； and when it is desired to record a sentence the spindle is started； and you speak into the mouthpiece。 The tympanum vibrates under your voice； and the stylus； partaking of its motion； digs into the yielding surface of the wax which moves beneath； and leaves a tiny furrow to mark its passage。 This is the sonorous record which； on being passed under the stylus of the reproducing tympanum； will cause it to give out a faithful copy of the original speech。 A flexible india… rubber tube； branching into two ear…pieces； conveys the sound emitted by the reproducing diaphragm to the ears。 This trumpet is used for privacy and loudness； but it may be replaced by a conical funnel inserted by its small end over the diaphragm； which thereby utters its message aloud。 It is on this plan that Edison has now constructed a phonograph which delivers its reproduction to a roomful of people。 Keys and pedals are provided with which to stop the apparatus either in recording or receiving； and in the latter case to hark back and repeat a word or sentence if required。 This is a convenient arrangement in using the phonograph for correspondence or dictation。 Each instrument； as we have seen； can be employed for receiving as well as recording； and as all are made to one pattern； a phonogram coming from any one； in any art of the world； can be reproduced in any other instrument。 A little box with double walls has been introduced for transmitting the phonograms by post。 A knife or cutter is attached to the instrument for the purpose of paring off an old message； and preparing a fresh surface of the wax for the reception of a new one。 This can be done in advance while the new record is being made； so that no time is lost in the operation。 A small voltaic battery； placed under the machine； serves to work the electric motor； and has to be replenished from time to time。 A process has also been devised for making copies of the phonograms in metal by electro… deposition； so as to produce permanent records。 But even the wax phonogram may be used over and over again； hundreds of times； without diminishing the fidelity of the reproduction。
The entire phonograph is shown in our figure。 ＇The figure is omitted from this e…text＇ It consists of a box； B； containing the silent electro…motor which drives the machine； and supporting the works for printing and reproducing the sounds。 Apart from the motive power； which might； as in the graphophone； be supplied by foot； the apparatus is purely mechanical； the parts acting with smoothness and precision。 These are； chiefly； the barrel or cylinder； C； on which the hollow wax is placed； the spindle； S； which revolves the cylinder and wax； and the two tympana； T； T'； which receive the sounds and impress them on the soft surface of the wax。 A governor； G； regulates the movement of the spindle； and there are other ingenious devices for starting and stopping the apparatus。 The tympanum T is that which is used for recording the sounds； and M is a mouthpiece； which is fixed to it for speaking purposes。 The other tympanum； T'； reproduces the sounds； and E E is a branched ear…piece； conveying them to the two ears of the listener。 The separate wax tube； P； is a phonogram with the spiral trace of the sounds already printed on its surface； and ready for posting。
The box below the table contains the voltaic battery which actuates the electro…motor。 A machine which aims at recording and reproducing actual speech or music is； of course； capable of infinite refinement； and Edison is still at work improving the instrument； but even now it is substantially perfected。
Phonographs have arrived in London； and through the kindness of Mr。 Edison and his English representative； Colonel G。 E。 Gouraud； we have had an opportunity of testing one。 A number of phonograms； taken in Edison's laboratory； were sent over with the instruments； and several of them were caused to deliver in our hearing the sounds which were
'sealed in crystal silence there。'
The first was a piece which