type. This form we named the zig-zag form, and referred to it in
that way in our notes. Its important advantage in guiding the
reproducing needle I first called attention to in the note on p.
9-Vol 1-Home Notes on March 29-1881, and endeavored to use it in my
early work, but encountered so much difficulty in getting a form of
reproducer that would work with the soft wax records without
tearing the groove, we used the hill and valley type of record more
often than the other.

In 1885, when the Volta associates were sure that they had a number of
practical inventions, they filed applications for patents. They also
began to look around for investors. After giving several demonstrations
in Washington, they gained the necessary support, and the American
Graphophone Co. was organized to manufacture and sell the machines. The
Volta Graphophone Co. was formed to control the patents.

The Howe sewing machine factory at Bridgeport, Connecticut, became the
American Graphophone plant; Tainter went there to supervise the
manufacturing, and continued his inventive work for many years. This
Bridgeport plant is still in use today by a successor firm, the
Dictaphone Corporation.

The work of the Volta associates laid the foundation for the successful
use of the dictating machine in business, for their wax recording
process was practical and their machines sturdy. But it was to take
several more years and the renewed work of Edison and further
developments by Berliner and many others, before the talking machine
industry really got under way and became a major factor in home
entertainment.[10]

PATENTS WHICH RESULTED FROM THE VOLTA LABORATORY ASSOCIATION

_Patent
Number_ _Year_ _Patent_ _Inventors_
229495 1880 Telephone call register C. S. Tainter
235496 1880 Photophone transmitter A. G. Bell,
C. S. Tainter
235497 1880 Selenium cells A. G. Bell,
C. S. Tainter
235590 1800 Selenium cells C. S. Tainter
241909 1881 Photophonic receiver A. G. Bell,
C. S. Tainter
243657 1881 Telephone transmitter C. S. Tainter
289725 1883 Electric conductor C. S. Tainter
336081 1886 Transmitter