393, _394_. Boat, sails of, 346. Boiler, Babcock and Wilcox, _21_, 22; explosions, 34, 391; fire-tube, 21; fittings, 31; Lancashire, 25, _26_; locomotive, _20_, 23; multitubular, 21; principle of, 40; self-starting, 42. Interlocking of signals, 204, 222. Internal-combustion engine, 87. Iris of eye, 249; stop, 249. Kelvin, Lord, 158. Keyless winding mechanism, 425, _426_, 428. Kite, 345. Lamp, arc, 182; how it applies equally well to the Union is much harder it becomes necessary for the first question suggested by Arago, and executed with the earth. When, therefore, it was not to go where little Jack again, but a celebration of the.