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

by Charles T. Porter

I had another client, a Mr. Hastings, who had invented a stone-dressing machine, which he had patented, and the patent for which he wanted to dispose of. He had a working model of his invention, which was operated for visitors in the shop where it was built. He invited me to go and see it, which I did, and it certainly worked very well indeed. I recalled afterwards that the stone was carefully bedded on the table of the machine. I was quite fascinated with it and took some friends to see it, who were equally captivated, and the result was that we bought the patent. To make sure of its value, however, I first called with Mr. Hastings on Mr. Munn, his patent solicitor, and received Mr. Munn’s assurance that he had a very high opinion of it.

I gradually abandoned my law business, and devoted myself to the exploitation of this invention. I put into it all the money I had and all that I could borrow. After a while a large working machine was completed for us, the drawings for which I had made by a German draftsman, and which was built under my direction at the works of Mott & Ayers, near the foot of West Twenty-sixth Street. When this machine was finished the parties in interest assembled at these works to see it tried.

One experiment was enough. I had put into the machine a stone that was quite a foot thick and which was supported at two points. At the first cut made across this stone it broke in two in the middle. I found myself, in the words of President Cleveland, “confronted not by a theory but by a condition.” The machine was absurd. The patent was worthless. The enterprise was a failure. Our money had all been thrown into the sea. Nothing could be done unless I did it; and I knew nothing of mechanics, of machine design or construction, or of mechanical drawing, except the little that I had picked up in the works of Mott & Ayers while this machine was in process of construction. I should say, however, that the head draftsman in that establishment had given me some instruction in mechanical drawing, so that I knew the use of the instruments and what kind of ink to use.

I cannot recollect that I was in the least cast down or discouraged. I cannot now account for my confidence. I believed that the fundamental features of this machine were correct. These were: cutting stone by a blow given by a hammer moving in an inclined direction, and which was thrown up by a cam and thrown down by springs. The more I reflected upon it the more I became convinced that a successful stone-dressing machine could be made on those general lines, and in no other way; and I also became impressed with what seems the almost absurd conviction that I could make it.

The machine that broke the stone had a broad hammer—a cast-iron plate with tongues on the sides running in grooves in a frame, and to the end of which a long steel blade was bolted. My first idea was to divide the single broad hammer into several hammers working side by side and striking their blows successively; the second was to separate the hammers from the tool-holders, the third, to employ the same tools that were used by stone-cutters, namely, the point, tooth-chisel and drove, and to give them as nearly as possible the same blow that was given to them by the workman, and the fourth, to give to the tools only the blow necessary to do their work.

I infused my own enthusiasm into my associates to such a degree that they agreed to put up the money and let me try the experiment. That also is something that I now wonder at.

The most influential member of this devoted band was George T. Hope, President of the Continental Fire Insurance Co., a gentleman whom I shall have frequent occasion to mention, and who remained my steadfast friend till his death, which occurred soon after the close of my engineering career.

I set about my work in this manner. My house, on the south side of Twenty-second Street west of Seventh Avenue, had been arranged in its construction to use the extension room back of the parlor as a dining-room. That left the front basement available for me. This I equipped for a drawing-office, and set myself at work to learn mechanical drawing, and at the same time to design this machine. I bought a Scotch instruction book, and a sheet of “antiquarian” drawing-paper. In those days all drawings were made on white linen paper, and this was nearly the largest size that was made, and cost 75 cents a sheet. My principal drawing-implement was india-rubber. As my plans grew in my mind I had to rub out my preceding sketches. I spent a great deal of my time in visiting the large engineering works on the East River—the Allaire Works, the Morgan Works and the Novelty Works—and studying tools and machines and principles and methods of construction. I tried to get my mind saturated with mechanics. I finally succeeded in producing the design, this vertical section of which I have sketched from memory after fifty years.

It will be seen that this machine was massive in its construction. This was required on account of the speed—300 rotations of the shaft per minute—at which I had determined to run it. This was my first employment of high speed.