When seven years old he was taken by his father to Barrow, near Barton-on-Humber, where Sir Rowland Winn had another residence and estate. Henry Harrison was still acting as the baronet's carpenter and joiner. In course of time young Harrison joined his father in the workshop, and proved of great use to him. His opportunities for acquiring knowledge were still very few, but he applied his powers of observation and his workmanship upon the things which were nearest him. He worked in wood, and to wood he first turned his attention. He was still fond of machines going upon wheels. He had enjoyed the sight of the big watch going upon brass wheels when he was a boy; but, now that he was a workman in wood, he proposed to make an eight-day clock, with wheels of this material. He made the clock in 1713, when he was twenty years old,[4] so that he must have made diligent use of his opportunities. He had of course difficulties to encounter, and nothing can be accomplished without them; for it is difficulties that train the habits of application and perseverance. But he succeeded in making an effective clock, which counted the time with regularity. This clock is still in existence. It is to be seen at the Museum of Patents, South Kensington; and when we visited it a few months ago it was going, and still marking the moments as they passed. It is contained in a case about six feet high, with a glass front, showing a pendulum and two weights. Over the clock is the following inscription: "This clock was made at Barrow, Lincolnshire, in the year 1715, by John Harrison, celebrated as the inventor of a nautical timepiece, or chronometer, which gained the reward of 20,000L., offered by the Board of Longitude, A.D. 1767. "This clock strikes the hour, indicates the day of the month, and with one exception (the escapement) the wheels are entirely made of wood." This, however, was only a beginning. Harrison proceeded to make better clocks; and then he found it necessary to introduce metal, which was more lasting. He made pivots of brass, which moved more conveniently in sockets of wood with the use of oil. He also caused the teeth of his wheels to run against cylindrical rollers of wood, fixed by brass pins, at a proper distance from the axis of the pinions; and thus to a considerable extent removed the inconveniences of friction.