During the later years of Mr. Corliss's life he devoted much time and thought to inventing improved pumps to be used in connection with city waterworks, "for forcing water to higher levels." He made for the city of Providence a rotary pump for high service which worked automatically, keeping the pipes in the upper sections of the city full at all times whether much or little water was used. This ingenious pump was visited by mechanics from all parts of the world. Only a few years before his death Mr. Corliss built another pump, an account of which was published some years ago. This account included the following incident: "I went down to Pettaconsett, the other day, to see the foundations of the building that Mr. Corliss is putting up there for the new pumping engine which he has engaged to put in for this city. I found that, in digging for the foundations, they came upon a deep bed of quicksand. Mr. Corliss, ever fertile in expedients to overcome obstacles, instead of driving down wooden piles, sunk in this quicksand great quantities of large cobblestones. These were driven down into the sand with tremendous force by a huge iron ball weighing four thousand pounds. I said: 'Mr. Corliss, why did not you drive wooden piles on which to build your foundation?' "'Don't you see,' said he, 'that the piles _have no discretion_, and that the cobblestones have?' "'I don't think I understand you, Mr. Corliss,' was my reply. "'If you drive a pile,' said he, '_it goes where you drive it, and nowhere else_; but a cobblestone will seek the softest place and _go where it is most needed_. It therefore has discretion, and better answers the purpose.' "I went away musing that the wooden 'piles' and the 'cobblestones' represent two classes of boys. 'The piles,' said Mr. Corliss, 'have _no discretion_, and _go only where they are driven_.' I think I have seen boys who represented this quality. 'But the cobblestones go _where they are the most needed_.' When boys fit themselves to go where they are the most needed, they will be pretty likely to meet with tolerably good success in life." The great service Mr. Corliss has rendered to the world through his inventions is shown by the awards made to him from the highest scientific authorities. At the Paris Exposition (1867) he received the highest competitive prize in competition with more than a hundred engines. A great English engineer, one of the British commissioners at the Exposition, said: "The American engine of Mr. Corliss everywhere tells of wise forethought, judicious proportion, sound execution, and exquisite contrivance." The American Academy of Arts and Sciences in 1870 awarded to Mr. Corliss the Rumford Medal. This medal was presented by Dr. Asa Gray, who said: "No invention since Watt's time has so enhanced the efficiency of the steam engine as this."