Edison's Method In Inventing - 6

Edison's Method In Inventing - 6

 The laboratory note-books do not always tell the whole story or meaning of an

experiment that may be briefly outlined on one of their pages. For example, the early

filament made of a mixture of lampblack and tar is merely a suggestion in the notes, but

its making afforded an example of Edison's pertinacity. These materials, when mixed,

became a friable mass, which he had found could be brought into such a cohesive, puttylike

state by manipulation, as to be capable of being rolled out into filaments as fine as

seven-thousandths of an inch in cross-section. One of the laboratory assistants was told to

make some of this mixture, knead it, and roll some filaments. After a time he brought the

mass to Edison, and said:

"There's something wrong about this, for it crumbles even after manipulating it with my

fingers."

"How long did you knead it?" said Edison.

"Oh! more than an hour," replied the assistant.

"Well, just keep on for a few hours more and it will come out all right," was the

rejoinder. And this proved to be correct, for, after a prolonged kneading and rolling, the

mass changed into a cohesive, stringy, homogeneous putty. It was from a mixture of this

kind that spiral filaments were made and used in some of the earliest forms of successful

incandescent lamps; indeed, they are described and illustrated in Edison's fundamental

lamp patent (No. 223,898).

The present narrative would assume the proportions of a history of the incandescent

lamp, should the authors attempt to follow Edison's investigations through the thousands

of pages of note-books away back in the eighties and early nineties. Improvement of the

lamp was constantly in his mind all those years, and besides the vast amount of detail

experimental work he laid out for his assistants, he carried on a great deal of research

personally. Sometimes whole books are filled in his own handwriting with records of

experiments showing every conceivable variation of some particular line of inquiry; each

trial bearing some terse comment expressive of results. In one book appear the details of

one of these experiments on September 3, 1891, at 4.30 A.M., with the comment:

"Brought up lamp higher than a 16-c.p. 240 was ever brought before--Hurrah!"

Notwithstanding the late hour, he turns over to the next page and goes on to write his

deductions from this result as compared with those previously obtained. Proceeding day

by day, as appears by this same book, he follows up another line of investigation on

lamps, apparently full of difficulty, for after one hundred and thirty-two other recorded

experiments we find this note: "Saturday 3.30 went home disgusted with incandescent

lamps." This feeling was evidently evanescent, for on the succeeding Monday the work

was continued and carried on by him as keenly as before, as shown by the next batch of

notes.

This is the only instance showing any indication of impatience that the authors have

found in looking through the enormous mass of laboratory notes. All his assistants agree

that Edison is the most patient, tireless experimenter that could be conceived of. Failures

do not distress him; indeed, he regards them as always useful, as may be gathered from

the following, related by Dr. E. G. Acheson, formerly one of his staff: "I once made an

experiment in Edison's laboratory at Menlo Park during the latter part of 1880, and the

results were not as looked for. I considered the experiment a perfect failure, and while

bemoaning the results of this apparent failure Mr. Edison entered, and, after learning the

facts of the case, cheerfully remarked that I should not look upon it as a failure, for he

considered every experiment a success, as in all cases it cleared up the atmosphere, and

even though it failed to accomplish the results sought for, it should prove a valuable

lesson for guidance in future work. I believe that Mr. Edison's success as an experimenter

was, to a large extent, due to this happy view of all experiments."

Edison has frequently remarked that out of a hundred experiments he does not expect

more than one to be successful, and as to that one he is always suspicious until frequent

repetition has verified the original results.