d submit a few sketches
of what he would propose to do. He brought three drawings to Edison, who
examined them and said none of them would answer. The engineer remarked
that it was too bad, for there was no other way to do it. Mr. Edison
turned to him quickly, and said: "Do you mean to say that these drawings
represent the only way to do this work?" To which he received the reply:
"I certainly do." Edison said nothing. This happened on a Saturday. He
followed his usual custom of spending Sunday at home in Orange. When he
returned to the works on Monday morning, he took with him sketches he
had made, showing FORTY-EIGHT other ways of accomplishing the desired
operation, and laid them on the engineer's desk without a word.
Subsequently one of these ideas, with modifications suggested by some of
the others, was put into successful practice.

Difficulties seem to have a peculiar charm for Edison, whether they
relate to large or small things; and although the larger matters have
contributed most to the history of the arts, the same carefulness of
thought has often been the means of leading to improvements of permanent
advantage even in minor details. For instance, in the very earliest days
of electric lighting, the safe insulation of two bare wires fastened
together was a serious problem that was solved by him. An iron pot over
a fire, some insulating material melted therein, and narrow strips of
linen drawn through it by means of a wooden clamp, furnished a readily
applied and adhesive insulation, which was just as perfect for the
purpose as the regular and now well-known insulating tape, of which it
was the forerunner.

Dubious results are not tolerated for a moment in Edison's experimental
work. Rather than pass upon an uncertainty, the experiment will be
dissected and checked minutely in order to obtain absolute knowledge,
pro and con. This searching method is followed not only in chemical or
other investigations, into which complexities might naturally enter,
but also in more mechanical questions, where simplicity of construction
might naturally seem to preclude possibilities of uncertainty. For
instance, at the time when he was making strenuous endeavors to obtain
copper wire of high conductivity, strict laboratory tests were made of
samples sent by manufacturers. One of these samples tested out poorer
than a previous lot furnished from the same factory. A report of this to
Edison brought the following note: "Perhaps