Mr. Ferguson told me the best piece-work story I ever heard. He said he had a contract for making a large number of the bases for the columns of the elevated railroad; these castings were quite large and complicated. He gave the job to his best molder, but the man could turn out only one a day. He thought it was slow work and spoke to him about it, but he protested that was all he could make. Mr. Ferguson found he could never complete his contract at that rate, and as he was paying the man three dollars a day, he told him he would pay him three dollars for each perfect casting and asked him to do his best and see how many he could turn out. The man employed a boy to help him, and by systematizing his work he turned out six perfect castings every day and drew his eighteen dollars with supreme indifference. This is a big story to swallow, but the incident was then recent. I had the story from Mr. Ferguson himself, and he was a sterling, reliable man, so that there could be no doubt as to its absolute truth. CHAPTER XVII Mr. Allen’s Invention of his Boiler. Exhibition at the Fair of the American Institute in 1870. At that time the “Field boiler tubes” were attracting considerable attention in London. These were designed to prevent the water from being lifted from the closed bottom of vertical tubes over the fire, which would cause them to be burned out. The Field tubes were smaller internal tubes, provided at the upper end with three wings which centered them in the middle of the external tubes, in which they reached nearly to the bottom. They were made slightly bell-mouthed at the top. The circulation was down the internal tube and upwards, through the annular space. The bell mouth prevented these currents from interfering with each other. One morning Mr. Allen said to me that he had an idea that by inclining the tubes at a small angle from the vertical a better circulation would be got than in the Field tubes. He thought the steam as fast as formed would all go to the upper side of the inclined tubes, and would rush up along that surface without driving the water before it, and so the water would always be at the bottom of the tube, no matter how hard the boiler was fired. I was struck with the idea and determined to test it. I got the largest test-tube I could find, 1¹⁄₄ inches in diameter and 15 inches long, and set it in an adjustable support, and applied the flame of four Bunsen burners, bunched together, at the bottom. In a vertical position the water was instantly thrown clean out of the tube. At about the angle of 20 degrees Mr. Allen’s idea was completely realized. The bubbles of steam united in a continuous stream on the upper side and rushed up with no water before them. With the most rapid generation of steam the water remained solid at the bottom of the tube. The sight was a very interesting one. I reasoned that if this satisfactory result was got under a short column of water, and only the pressure of the atmosphere