Engineering reminiscences contributed to "Power" and "American machinist"

by Charles T. Porter

In the English naval exhibit three men made an exhibition of their childish extravagance. Models were shown of a fleet of eight vessels, each quite 10 feet long, completely and superbly finished inside and out, and entitled “England’s Fleet of the Future.” The vessels, full rigged, were built by Robert Napier. They were provided with engines made by John Penn, and carried broadsides of Whitworth guns. Recalled in the light of to-day, this costly show appears supremely ridiculous. It did not present a single feature that has not long since vanished and become almost forgotten. Both the prince and the toys furnish a lesson to the moralist. How swiftly, as by a cyclone, has all that each represented been swept away forever! What is there, in governments or in mechanism, that shall endure?

It was my good fortune one day in the latter building to meet Admiral Farragut. I heard him say, respecting this proud fleet, “When it is built, some Yankee will come with a torpedo and blow it out of the water.” One other terse reply of the old hero which I then heard is worthy to be recorded. He was asked his opinion of the monitor. “A machine to drown a man in like a rat, sir,” was his answer.

About midsummer I received an application from the firm of Ducommen et Cie. of Mulhouse, a city in the southern part of Alsace, and an important manufacturing center, whose people also had no foreboding of what was so soon to befall them, for a concession to manufacture my engines in France. They had a large exhibit at the exposition, and impressed me quite favorably. I consulted with Mr. Hoyle and replied, deferring action until a later period of the exposition. Some time in September, not having received any other application, I accepted this one. There I made a mistake. Just before the close of the exposition I received a very flattering letter from the firm of Farcot et Cie., the most eminent stationary engine-builders in France, and who showed the largest engine at the exposition. Their works were near Paris, and on their invitation, in company with Mr. Hoyle, I had visited them. They stated that, having observed closely the performance of the engine through all these months, they had become convinced of its excellent and durable qualities, and solicited the right to manufacture the engine in France. I had to pay the penalty for my premature action in explaining to them with deep regret that this right was already disposed of. My regret was deepened when, in the course of the following winter, I received in Manchester copies of drawings according to which Ducommen et Cie. proposed to construct the engines. The changes they had made, all in the direction of complication, amazed me. It seemed to have rained bolts and nuts. Every constructive requirement of a successful high-speed engine was ignorantly sacrificed. After full consultation Mr. Hoyle and I agreed that the case was hopeless, that they would never do anything; and they never did. I have no photographs of the Paris Exposition. It was a very singular thing that none were taken there, so far as I ever heard.

Near the close of the exposition I had another visit from Mr. Allen. He had been sent over by our associates to see for himself and to report to them what I had really accomplished. He stayed with me a little while after our return to Manchester. Mr. Whitworth treated us with the greatest civility. On his invitation we rode out to his country home and spent the day with him. This visit is worth recording. His estate lay in Derbyshire, adjacent to Chatsworth, the well-known seat of the Duke of Devonshire. It occupied a rather broad valley, extending to the sky-line of high ranges of hills on each side, and comprised three thousand acres. He told me that three adjoining estates fell into the market, one after another, and he succeeded in getting the whole of them. In the middle of this valley was a lower isolated hill, containing stone quarries that had been worked from time immemorial, and which, when he bought, were surrounded by unsightly heaps of débris. Mr. Whitworth had closed the quarries, covered these heaps with earth on which trees were then growing, and transformed the whole into most picturesque ornamental grounds. After lunch Mr. Whitworth took his cane and, with a step as sprightly as a schoolboy’s, led us a tramp over this region. In the quarries he had formed galleries at different elevations. Finally, at the top of the hill, commanding views of his whole estate, he had leveled a space about 100 by 200 feet and surrounded it with a rustic battlement of rocks. Here a grassy sward smooth and level as a billiard table was used as a croquet ground, this being at that time a universal outdoor game in England. He had a democratic park. It had no wall, and wire fences were as yet unknown, so he could not keep deer. But on his fields we saw many cattle grazing. He told us he was raising blooded stock, and expected the next year to commence annual sales. We observed the very pleasant house beautifully located in the valley, but he told us he was planning to remove it and build a baronial hall in its place. I learned afterwards from Mr. Hoyle that he had for some time kept two London architects employed on designs for this hall, which designs he then employed another draftsman to combine into a plan to suit himself, but had not as yet determined on anything. As he was an old man, and had no one in the world to leave this estate to, I could account for his devotion to it only by his restless temperament, that must always find some new outlet for his energy.

I, however, did not want him to expend any of this energy in getting a steam-engine to suit him, and so the passing months brought us no nearer to an agreement. My experience with Ducommen et Cie. confirmed me in my decision not to let the mechanical control of the engine in England pass out of my hands, and Mr. Hoyle told me that he could not advise me to do so. Mr. Whitworth was at that time in the death agonies of his artillery system, and I did not meet him, but I learned through Mr. Hoyle that he was highly indignant at me for presuming to take the position I had done, and was immovably fixed in his own.

CHAPTER XIV

Study of the Action of Reciprocating Parts. Important Help from Mr. Frederick J. Slade. Paper before Institution of Mechanical Engineers. Appreciation of Zerah Colburn. The Steam Fire Engine in England.

After the close of the Paris Exposition I devoted myself in earnest to the study of the action of the reciprocating parts of the engine, and will here give a sketch of its development. In the high-speed steam-engine the reciprocating parts were found to be a most essential feature. Besides transmitting the pressure of the steam to the crank they perform quite another office. It is their inertia, relieving the crank from shocks on the dead centers, and equalizing the distribution of the pressure on it through the stroke, that makes the high-speed engine possible. I employed this inertia before I knew anything about it. I had been occupied with the subject of balancing. I had demonstrated practically that the centrifugal force of a weight equal to that of the reciprocating parts, opposite the crank and at the same distance from the center as the crank-pin, perfectly balanced a horizontal engine, and had shown this fact conclusively at this exposition.

The problem before me was, “What is it that makes my engine run so smoothly?” I am not a mathematician, and so could not use his methods. I got along by graphic methods and study of the motion of the piston controlled by the crank. My recollection of the several steps of my progress is quite indistinct. One thing I do remember distinctly, and that is the help that I got from my friend Frederick J. Slade, who was younger than I, but who died several years ago. Mr. Slade was a mathematical genius. The firm of Cooper, Hewitt & Co. were at a later date the pioneer makers in the United States of wrought-iron beams and other structural shapes; and all their designs and computations were the work of Mr. Slade. I had formed his acquaintance in London in ’63. I met him again in Paris in ’67. He was then in France in the employ of Abram S. Hewitt, investigating the Siemens-Martin process of steel manufacture. He took much interest in the engine. One day he brought to me a diagram representing the two now famous triangles, and a demonstration of them which he had made, showing that the ordinates, representing the acceleration or retardation of the piston motion at every point, if erected on the center line of the engine, terminate in a diagonal line, which, with a connecting-rod of infinite length, would cross this center line at its middle point.