Figure 5.- Experimental Graphofhonk photo- 

 graphed in 1884 at the \'olta Laboratory. This is 

 similar to one preserved at the Smithsonian Institu- 

 tion. {Smilhsonian photo 44312-Z).) 



least 8 feet from the phonograph." The point of the 

 jet is glass, and could be directed at a single groove. 



The other experimental Graphophones indicate 

 an amazing range of experimentation. While the 

 method of cutting a record on wax was the one later 

 exploited commercially, everything else seems to 

 have been tried at least once. 



The following was noted on Wednesday, March 

 20, 1881 : "A fountain pen is attached to a diaphragm 

 so as to be vibrated in a plane parallel to the axis 

 of a cylinder — The ink used in this pen to contain 

 iron in a finely divided state, and the pen caused to 

 trace a spiral line around the cylinder as it turned. 

 The cylinder to be covered with a sheet of paper 

 upon which the record is made. . . . This ink . . . can 

 be rendered magnetic by means of a permanent 

 magnet. The sounds were to be reproduced by 

 simply substituting a magnet for the fountain pen . . ." 



The result of these ideas for magnetic reproduction 

 resulted in patent 341287, granted on May 4. 1886; 

 it deals solely with "the reproduction, through 

 the action of magnetism, of sounds by means of 

 records in solid substances." 



Figure 6. — Another Experimental Graphophone, 

 photographed at the V'olta Laboratory in 1884. 

 [Smithsonian photo 443 1 2-F.) 



The air jet used in reproducing has already l)ccn 

 descriljed. Other jets, of molten metal, wax, and 

 water, were also tried. On Saturday. May 19. 1883, 

 Tainter wrote (see fig. 3): 



Made the following experiment today: 



The cylinder of the Edison phonograph was covered with 

 the coating of paraffine-wax and then turned off true and 

 smooth. 



A cutting style .\.. secured to the end of a lever B was then 

 adjusted over the cylinder, as shown. Lever B was pivoted 

 at the points C-D. and the only pressure exerted to force the 

 style into the wax was due to die weight of the parts. 



Upon the top of A was fixed a small brass disk, and 

 immediately over it a sensitive water jet adjusted, so that the 

 stream of water at its sensitive part fell upon the center of the 

 brass disk. 



The Phonograph c\linder E, was rotated while words and 

 sounds were shouted to the support to which the water jet 

 was attached, and a record that was quite visible to the 

 unaided eye was the result. 



The tape recorder, an unusual instrument which re- 

 corded inechanically on a ',s-inch strip of wax-cov- 

 ered paper, is one of the machines descrilx-d and illus- 

 trated in U. S. patent 341214, dated May 4, 1886 

 (sec fig. 4). The strip was coated by dipping it in a 



P.M'F.R 5: PHONOGRAPH .\T .ALEXANDER GR.AHAM BELLS VOLTA LABORATORY 



75 



