Edison Portland Cement - 3

Edison Portland Cement - 3

 Among the many innovations appearing in this plant are two that stand out in bold relief

as indicating the large scale by which Edison measures his ideas. One of these consists of

the crushing and grinding machinery, and the other of the long kilns. In the preceding

chapter there has been given a description of the giant rolls, by means of which great

masses of rock, of which individual pieces may weigh eight or more tons, are broken and

reduced to about a fourteen-inch size. The economy of this is apparent when it is

considered that in other cement plants the limit of crushing ability is "one-man size"--that

is, pieces not too large for one man to lift.

The story of the kiln, as told by Mr. Mallory, is illustrative of Edison's tendency to upset

tradition and make a radical departure from generally accepted ideas. "When Mr. Edison

first decided to go into the cement business, it was on the basis of his crushing-rolls and

air separation, and he had every expectation of installing duplicates of the kilns which

were then in common use for burning cement. These kilns were usually made of boiler

iron, riveted, and were about sixty feet long and six feet in diameter, and had a capacity

of about two hundred barrels of cement clinker in twenty-four hours.

"When the detail plans for our plant were being drawn, Mr. Edison and I figured over the

coal capacity and coal economy of the sixty-foot kiln, and each time thought that both

could he materially bettered. After having gone over this matter several times, he said: `I

believe I can make a kiln which will give an output of one thousand barrels in twentyfour

hours.' Although I had then been closely associated with him for ten years and was

accustomed to see him accomplish great things, I could not help feeling the improbability

of his being able to jump into an old-established industry--as a novice--and start by

improving the `heart' of the production so as to increase its capacity 400 per cent. When I

pressed him for an explanation, he was unable to give any definite reasons, except that he

felt positive it could be done. In this connection let me say that very many times I have

heard Mr. Edison make predictions as to what a certain mechanical device ought to do in

the way of output and costs, when his statements did not seem to be even among the

possibilities. Subsequently, after more or less experience, these predictions have been

verified, and I cannot help coming to the conclusion that he has a faculty, not possessed

by the average mortal, of intuitively and correctly sizing up mechanical and commercial

possibilities.

"But, returning to the kiln, Mr. Edison went to work immediately and very soon

completed the design of a new type which was to be one hundred and fifty feet long and

nine feet in diameter, made up in ten-foot sections of cast iron bolted together and

arranged to be revolved on fifteen bearings. He had a wooden model made and studied it

very carefully, through a series of experiments. These resulted so satisfactorily that this

form was finally decided upon, and ultimately installed as part of the plant.