So boy and man progressed together in their educational
partnership.

When George Stephenson became chief enginewright of the
Killingworth collieries at one hundred pounds a year he thought
he had reached the summit of his ambition. The duties of the
position made less demand upon him for manual labor, and left him
time to carry out some of his mechanical ideas. He devised new
hoists and pumps for the mines, and then applied himself to the
ever-present problem of cheapening the transportation of the
coals between pit mouth and ship side. One of his first
improvements of this sort was a gravity railway, so arranged that
the loaded cars, running down to the river by their own weight,
furnished the power to draw the empty cars to the summit again by
cable. When George Stephenson took up the problem of
perfecting a "traveling steam engine" he had the advantage of
knowing what had been accomplished by other experimenters. For
fifty years inventors had been turning out steam engines of
considerable promise in the model stage, but of little practical
performance. Indeed, about 1803, a Cornishman named Trevithick
had produced a locomotive which was used for a time to transport
metal and ore to the Pen-y-darran iron works in South Wales. The
heavy engine so damaged the tracks that it was soon dismounted
and degraded to the work of a steam pump. In 1812 a cog-wheel
locomotive, invented by a Mr. Blenkinsop, began running in a
colliery a few miles out of Leeds, and served very well its
purpose to haul heavy trains almost as fast as a horse could
walk. The next year a Derbyshire mechanic produced a "Mechanical
Traveler," the legs of which were moved alternately by steam, but
the bursting of its boiler on its trial trip put an end to its