" Yet these type experiments became rarer the
1890s progressed; there was longer the time money find
a substitute for ivory, rubber, silk, mother pearl. Yet order finance
the manufacturing well the R&D the phonograph and ore
separation, Edison had cut back some the more
speculative efforts underway. The research effort was concentrated into
these three basic areas, Table illustrates:
. Some projects would practical campaigns,
based identified problems with known goals, and others would
be more speculative basic research with clearly defined
objectives. Edison's strategy was spread his money and
experiments over group projects and use the profits one
to finance the development another. Work was ended the cotton
picker and the hearing aid. Edison still maintained long-term speculative
experiments for his own personal interest; including
experiments etheric force and other electromagnetic
phenomena that had been suggested his study the "Edison
Effect. The pyro-magnetic generator was
abandoned.VI-12
with several research and manufacturing operations running at
the same time.^
The Edison enterprise began the 1890s the foundation
of three main businesses: phonographs, ore separation, and
electrical products