Mr. Bishop replied to me: “It does project, Mr. Porter; it projects seven eighths of an inch over the port at each end of its stroke, for I have measured it.” I rushed up to the drawing-office and called for the horizontal sectional drawing of that cylinder, and there I saw the piston not only drawn, but figured--projecting seven eighths of an inch over the port. I felt as though I were sinking through the floor. That was what had ruined my Boston exhibition and sent me home disgraced and broken-hearted and the badly fitting piston, shameful as that was, had nothing to do with it. The first question that occurred to me was: “How came this drawing to exist and I to know nothing about it?” The answer to this question was simple. When the first pair of Willimantic engines was started I was disappointed in their economy, and made up my mind that the excessive waste room was accountable for it. The proportion of cross-section area to the stroke being fifty per cent. greater than in my table of sizes increased in the same degree the proportion of waste room to the piston displacement. I felt that there was need here for improvement. By far the greatest amount of waste room was in the exhaust ports. I accepted a modification of the exhaust valves by which this item of the waste room was reduced fully one half and made a new pair of cylinders for this engine. The improvement in the economy was so marked that I determined to change the exhaust valves of all the engines. Only the exhaust valves and ports needed to be changed. These were drawn anew in pencil and carefully studied and approved of by me. It was necessary that the entire combined cylinder drawing should be retraced, but this, except only the exhaust ports and valves, was to be copied over the existing tracings. This did not require my attention, and I gave no thought to it. Here was the superintendent’s opportunity. In copying these tracings he had only to move the straight line representing each face of the piston on the longitudinal section of the cylinder seven eighths of an inch, thus adding this amount to the piston at each end, and shorten the cylinder heads to correspond, and the job was done; and there did not exist among the large number of persons in the drawing-office and shop who must have been aware of this change, loyalty enough to let me know anything about it. We had also recently finished two engines for the Cocheco Mill at Dover, N. H., and about this time we received a letter from the superintendent of that mill expressing his admiration of the engines in every other respect, but complaining of a bad thump in the cylinders. He said he would be glad to invite the superintendents of other mills to see them, but he could not show the engines to anybody until that thump was cured.