[D8850ABC], Letter from Ageron Gap to George Edward Gouraud, March 21st, 1888


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[D8850ABC], Letter from Ageron Gap to George Edward Gouraud, March 21st, 1888

Editor's Notes

"In accordance with my former communications to you, which you were kind enough to receive favorably, I beg to send you the drawing of my phonograph which realizes the following conditions: ### I. The registering & reproduction of sounds during long hours without changing anything which makes possible the phongramic impression of the largest books. ### 2. The cheapness of the machine itself & of the registering paper & the convenience for sending phonograms. ### One of the two drawings I send you represents the machine I have made as seen from the left of a person speaking into the receiver; the second represents the plan, that is to say the apparatus as seen vertically downwards. I have not put any figures on these drawings as with the following explanations it will be easy for you to understand the whole. ### In order to register the sounds I use Edison's speaker with his acoustic receiver & bodkin or style. This bodkin instead of tracing the vibrations on a fixed cylinder covered with hardened wax or any other impressible material, traces them on a pasteboard strip thick enough to have grooves made of the same depth as those traced on Edison's cylinder (old system). This pasteboard so prepared is covered with a tin strip the borders of which are stuck on the pasteboard strip. ### This strip is the most delicate part of my process. The two edges must be quite parallel to each other & paralell also to the groove if not the bodkin would run off & that would be a great inconvenience. Therefore, to manufacture it in great quantity it is necessary to have a special plant composed of two cylinders arranged as a flattening-mill or as the instruments used by photographers for smoothing their photographic pasteboard as represented in its main points by the dawing n 2. Two knives would cut the pasteboard strip as it would come out of the flattening-mill & a perfectly prallel pasteboard strips could be obtained in that way. If this process did not answer the purpose the pasteboard could be out in strips of a given width tightly rolled up & placed against the surface plate of a lathe & then turned on either sides so as to give the boarders that parallelism which is indispensable; this done they should be put under the cylinders of the flattening-mill to have them grooved & then the last thing to do would be to cover them with a tin strip. ### For my experiments I have manufactured little pieces of these strips & after trial I have come to this conclusion that the strip by passing before the vibrating bodkin produced the same results as Edison's cylinder by turning round before the same bodkin. ### As the strip can be of an indefinite length & that moreover several parallel grooves can be disposed on the same strip it is not by hundreds that words so reproduced are to be recokened, but by thousands & even millions. ### The strip in rolling itself up protects the vibrations of a spire against any atomospheric agent & any other accident, so that in this respect also, for a more or less lengthy reproduction, it realizes a great improvement in Edison's new movable cylinders, very resisting in the interior but so very weak at the exterior that they must be handled with the greatest care. ### Had I had this strip made I should have betrayed myself & had I sent you my machine without it would have been sending you a useless tool, I, therefore, preferred sending you the two drawings above mentioned. They are both fulll size & consequently a seale would be useless. ### The organs of the apparatus are as follows: Two pulleys like those used for the rolling up of Morse's telegraph strips are superposed, between the two pulleys there is what I call a guide made of an iron roller mounted upon screw shaft a which is fixed to arm b turning round screw v so as to be well adjusted in front of the vibrating bodkin. A skew cutting out d in vertical wooden stand m, allows of that displacement around v. The borders of roller r are projecting so as to guide the strip & is the point of support in order to enable the bodkin of the receiver to impress its vibrations on the tin. ### The two pulleys one of which is used to un-roll the strip rolled up on the other vice versa, are composed I of shaft a which carries roller r of 0.06c in diameter & of an equal thickness with the width of the strip & consequently with the width of the part hollowed betwween the borders of the guide. This roller or disc is used to give to the first spire of the strip a sufficient diameter to prevent the rumpling of the latter or even its breaking on account of its thickness, an accident that would happen if it were rolled up (as a tailor's tape measure) on a very small shaft. This same dise is screwed so as to be able to have it always on the same plane as the guide & disc of the inferior pulley. It is held between two slabs p p screwed on the same shaft. These two slabs are used to give the rolling & unrolling the greatest exactness & must therefore be turned in the interior with precision. The outside one can be unscrewed so as to take off the rolled strip & send it. ### The strip must always be perfectly tight. I think that the shafts of the two pulleys being sufficiently held in their pillow-blocks the strain put upon them by the rolling up of the strip will not likely cause them to turn unevenly. However, a 'tendeur' could be placed above the guide & can be made like the one used in Morse's telegraph. And then to set the machine in motion crank m can be used by fixing it to the end of the shaft of the pulley to be set in motion. The strip itself is used as a transmission-strap. Moreover, this part of my apparatus being analogous to that of Morse's telegraph I suppose that I have made myself understood. ### I have already said that several grooves could be disposed on the strip so as to use its length several times. In this case it is necessary that the bodkin should displace itself parallely to the guide so as to adjust it in each longitudinal groove of the strip, therefore, the stand of the receiver is fixed to a small board placed on the table of the apparatus. This table is so made that the two bolts which sustain the small board can displace themselves in a parallel line to the guide in front of which is the vibrating bodkin, as you will see in the vertical plane drawing. ### It is useless telling you, Sir, that the crank is not to be seen in the apparatus & that it is necessary to apply a mover to it. As any silent mover will do, be it a clock work or electric one I leave out this point of construction. I do not say anything either about the speaker as it is similar to that of Edison & the new 'double speaker' of which so much good is said can be used instead. ### I have tried to apply wax on pasteboard strips but it cracks on account of the spiral grinding down, another material more convenient to the purpose ought to be found & that would be a great improvement as the strip would no longer have to be grooved before hand so that it would be easier to manufacture & therefore cheaper. I thought of Edison's movable cylinders, but probably the rolling up will also make it unpractical. ### I have not here the requisites to make chemical experiments I therefore can only show you now the strip covered with tin, leaving it to you to see whether it can be improved in the way above mentioned? ### As you see, Sir, the apparatus is very simple in itself & realizes, with the help of Edison's inventions which I have transformed, all the results that you obtain with your last apparatus & have a wider scope in its applications. ### I might have taken patents, I might have had my apparatus manufactured in Paris where I am urged to do so but I have refrained from a contest of improvements with 'l'illustre Edison' & that is my reason for taking this present step. ### If you believe in my apparatus you can from the above explanation have one made combining solidity with elegance & if you are satisfied with the results, about which I have no doubt, we might come to an understanding for its exploitation. ### As regards the complement, that is to say, my personal invention for the multiplication of impressible strips, which makes the daily phonogramic paper possible, I will wait & see how you will receive my present communications before I entrust you with my secret. ### I have moreover settled everything so that my inveintion can be put on the market at once should we not come to terms. ### Do not think, Sir, that in giving you this information I have in view a mercantile object. I write to you with the greatest sincerity & honesty belieiving that I can not do better than to repose my confidence in the representative of Mr. Edison & consequently in Mr. Edison himself. ### As regards the manufacturing of the phonogramic doll a reduction of the apparatus will answer the purpose and even in an ordinary "Juneau" doll a strip of a sufficient length can be rolled up to enable the doll to speak for a sufficient length of time. ### With refrence to the phonogramic telegraph you will also allow me to keep the matter to myself, just now. In your last letter you said you had your doubts about this & it is but natural, for the result of this last application is produced by the most unexpected means. ### On Tuesday next we shall have a fortnight holiday & I intend to avail myself of this opportunity to go to Paris. Should you not care to have my apparatus made in London at your expense, or in another word, should you not think fit to adopt it I am quite ready to have it manufactured myself & my parents will enable me to incur the necessary expenses for its construction. But in such a case our communications would be discontinued as I should have to sign the contract which that influential firm in Paris proposed that I should sign. ### I, therefore, should feel very much obliged to you, Sir, if you could let me know by Tuesday what you have decided. I have made inquiries to know whether the apparatus of which I send you a drawing is patentable & I find it is. I must tell you that independentsly, of the commercial result obtained by the strip I did not intend to use Edison's speaker, but one of my own invention which I must confess is not so practical as the new one." [unsigned]







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Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
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