The Edison disc record was composite blank and layer of
recording medium. [There are
several more these
uncataloged Building 2]
Robertson DISC PRESS
(beside lab table)
Figure 34. Use EDIS 477. probably would have
supervised the work test pressing. Use EDIS 4275. the case
of disc records, this was simple matter using hydraulic press with the
matrix attached imprint the grooves sound waves into record blanks. This press could have been used fuse these two layers
together for test purposes. Use EDIS 347.
LID MOLDS (on the floor) Figure 34.632 This could
have been done the southeast corner Building using hot plates and ice
chests. one experiment, shellac cylinders were heated 115°F for
one week and then returned room temperature and played. The
Robertson disc press this table was probably used for experimental rather than
production purposes (production would have gone large factory such as
Building 24) and therefore would surrounded experimental disc blanks
and fragments.
Experiments were conducted find out the effects heating and freezing on
record materials. Once the record material had been mixed and a
matrix (or mold was called the laboratory) the master recording
prepared, the task was then press numerous copies the original.
Experimental DISC (on table) Complements the disc press.
Object and Location Evidence Recommendation
Table 5
LAB TABLE (in place) Physical evidence; figure 34. Use EDIS 57263.
SCREW PRESS for discs (on
table)
Figure 34. Use EDIS 7505.
Steam HOT PLATES, (on
table)
Figure 34. Use EDIS 7496, EDIS 7489,
and EDIS 7496.
Albert Petit was heavily involved phonograph experiments and was experienced
in making matrices and using them presses.
220
.Table Pressing Records. Use EDIS 4218.
DISC FRAGMENT (on table) Complements the disc press.
632 Meadowcroft Reports, August 25, 1911 (in 1911, WOL)