Vibration.
An amusing incident occurred in connection with the building of the "Campania." On her engine trial she vibrated excessively, even dangerously, breaking some stanchions and deck plating. It was decided to ask Lord Kelvin, then Sir William Thomson, to investigate the cause of the vibration, and I was deputed to attend him upon the necessary trials on the Clyde. After several days' trials Sir William announced that the vibration would all disappear if the ship was loaded down. Three thousand tons of coal were put on board, and a large party of guests were invited for the trial trip. It was arranged that the ship should upon this trip start at a slow speed, at which there was no vibration, and when the guests were seated at lunch the directors were to quietly come on deck and the ship be put at full speed. This was no sooner done than she began to shake from stem to stern so violently that the whole of the guests streamed on deck enquiring what was the matter, and the speed of the ship had to be reduced. The vibration was afterwards cured by following the suggestion of our old Scotch engineer and altering the pitch of the screws, so that their revolutions did not synchronise with the vibratory period of the ship.
Some few years after this event I was invited to dine one Sunday evening at Balliol College, Oxford. After dinner I was taken into an adjoining room to wine by the president, Professor Cairns, well known as a great philosophical thinker and writer. On passing out of the dining hall a friend whispered to me, "I am sorry for you; the president never utters a word to his guest." We sat at a small table vis-à-vis. I tried to draw the president into conversation on several subjects, but failed lamentably. Eventually I asked him if he knew Lord Kelvin. He at once said he was an old friend; whereupon I told him the story of my experience on the "Campania." He became quite excited and interested. On my leaving the room my friend, who was a don on the classical side, again came up to me, and asked what we had been talking about. I answered "Vibration." He replied, "What is that? I never saw the president so interested and so excited before."