taken by a technical journal among its expert readers
had exactly the same result. Evidently the public does not agree with
the opinion expressed by the eccentric artist Blake in his "Marriage of
Heaven and Hell," when he said: "Improvement makes strange roads; but
the crooked roads without improvements are roads of Genius."

The product of Edison's brain may be divided into three classes. The
first embraces such arts and industries, or such apparatus, as have
already been treated. The second includes devices like the tasimeter,
phonomotor, odoroscope, etc., and others now to be noted. The third
embraces a number of projected inventions, partially completed
investigations, inventions in use but not patented, and a great many
caveats filed in the Patent Office at various times during the last
forty years for the purpose of protecting his ideas pending their
contemplated realization in practice. These caveats served their purpose
thoroughly in many instances, but there have remained a great variety of
projects upon which no definite action was ever taken. One ought to
add the contents of an unfinished piece of extraordinary fiction based
wholly on new inventions and devices utterly unknown to mankind. Some
day the novel may be finished, but Edison has no inclination to go
back to it, and says he cannot understand how any man is able to make a
speech or write a book, for he simply can't do it.

After what has been said in previous chapters, it will not seem so
strange that Edison should have hundreds of dormant inventions on his
hands. There are human limitations even for such a tireless worker as he
is. While the preparation of data for this chapter was going on, one of
the writers in discussing with him the vast array of unexploited things
said: "Don't you feel a sense of regret in being obliged to leave so
many things uncompleted?" To which he replied: "What's the use? One
lifetime is too short, and I am busy every day improving essential parts
of my established industries." It must suffice to speak briefly of a few
leading inventions that have been worked out, and to dismiss with
scant mention all the rest, taking just a few items, as typical and
suggestive, especially when Edison can himself be quoted as to them.
Incidentally it may be noted that things, not words, are referred to;
for Edison, in addition to inventing the apparatus, has often had to
coin the word to describe it. A large number of the words and phrase