The idea of submarine navigation is much older than 1624. Crude diving bells, and primitive leather diving helmets, with bladders to keep the upper end of the air tube afloat on the surface of the water, were used as early as the fourteenth century. William Bourne, an Englishman who published a book on “Inventions or Devices” in 1578, suggested the military value of a boat that could be sailed just below the surface of the water, with a hollow mast for a ventilator. John Napier, Laird of Merchiston, the great Scotch mathematician who invented logarithms, wrote in 1596 about his proposed “Devices of sailing under the water, with divers other devices and stratagems for the burning of enemies.” But the first man actually to build and navigate a submarine was a Dutchman: the learned Doctor Cornelius Van Drebel.[1] He was “a native of Alkmaar, a very fair and handsome man, and of very gentle manners.” Both his pleasing personality and his knowledge of science--which caused many to suspect him of being a magician--made the Netherlander an honored guest at the court of his most pedantic Majesty, King James I of England. Van Drebel was walking along the banks of the Thames, one pleasant evening in the year 1620, when he “noticed some sailors dragging behind their barques baskets full of fish; he saw that the barques were weighed down in the water, but that they rose a little when the baskets allowed the ropes which held them to slacken a little. The idea occurred to him that a ship could be held under water by a somewhat similar method and could be propelled by oars and poles.”[2] [Illustration: Cornelius Van Drebel. Reproduced from “Submarine Navigation, Past and Present” by Alan H. Burgoyne, by permission of E. P. Dutton & Company. ] Lodged by the king in Eltham Palace, and supplied with funds from the royal treasury, Van Drebel designed and built three submarine boats, between 1620 and 1624. They were simply large wooden rowboats, decked over and made water-tight by a covering of thick, well-greased leather. Harsdoffer, a chronicler of the period, declared that “King James himself journeyed in one of them on the Thames. There were on this occasion twelve rowers besides the passengers, and the vessel during several hours was kept at a depth of twelve to fifteen feet below the surface.” Another contemporary historian, Cornelius Van der Wonde, of Van Drebel’s home town, said of him: “He built a ship in which one could row and navigate under water from Westminster to Greenwich, the distance of two Dutch miles; even five or six miles or as far as one pleased. In this boat a person could see under the surface of the water and without candle-light, as much as he needed to read in the Bible or any other book. Not long ago this remarkable ship was yet to be seen lying in the Thames or London river.”