ified and indexed. Seemingly, Edison is the most careless,
indifferent and slipshod of men, but the real fact is that such a
thorough business general the world has seldom seen. If he wants, say,
the "Electrical Review" for March, Eighteen Hundred Ninety-One, he hands
a boy a slip of paper and the book is in his hands in five minutes.
Edison of all men understands that knowledge consists in having a clerk
who can quickly find the thing. In his hands the card-index has reached
perfection.

Edison has no private office, and his desk in the great library has not
had a letter written on it since Eighteen Hundred Ninety-five. "I hate to
disturb the mice," he said as he pointed it out indifferently.

He arrives at the stockade early--often by seven o'clock, and makes his
way direct to the Laboratory, which stands in the center of the campus.
All around are high factory buildings, vibrating with the suppressed roar
and hum of industry.

In the Laboratory, Edison works, secure and free from interruption unless
he invites it. Much of his time is spent in the Chemical Building, a low,
one-story structure, lighted from the top. It has a cement floor and very
simple furniture, the shelves and tables being mostly of iron. "We are
always prepared for fires and explosions here," said Edison in
half-apology for the barrenness of the rooms.

The place is a maze of retorts, kettles, tubes, siphons and tiny brass
machinery. In the midst of the mess stood two old-fashioned
armchairs--both sacred to Edison. One he sits in, and the other is for
his feet, his books, pads and paper.

Here he sits and thinks, reads or muses or tells stories or shuffles
about with his hands in his pockets. Edison is a man of infinite leisure.
He has the faculty of throwing details upon others. At his elbow, shod in
sneakers silent, is always a stenographer. Then there is a bookkeeper who
does nothing but record the result of every experiment, and these
experiments are going on constantly, attended to by half a dozen quiet
and alert men, who work like automatons. "I have tried a million schemes
that will not work--I know everything that is no good. I work by
elimination," says Edison.

When hot on the trail of an idea he may work here for three days and
nights without going home, and his wife is good enough and great enough
to leave him absolutely to himself. In a little room in the corner of the
Laboratory is a little iron cot and three gray army blankets.