a clock-face. Similar clocks were made in which sand was used
instead of water. The hour-glass was a time-measurer for many centuries
in Europe, and all the ancient literatures abound in allusions to the
rapid, unobserved, running away of its sands.

The next advance was the invention of the wheel-and-weight-clock, such
as has been in use ever since. The first instrument of this kind may
have been made by the ancients; but no clear allusion to its existence
has been discovered earlier than 996, when Pope Sylvester II. is known
to have had one constructed. It was Christian Huygens, the famous Dutch
philosopher, who applied, in 1658, the pendulum to the clock, and thus
led directly to those more refined and subtle improvements, which render
our present clocks and watches among the least imperfect of all human
contrivances.

George Graham, the great London clock-maker of Queen Anne's and George
the First's time, and one of the most noted improvers of the clock, was
born in 1675. After spending the first thirteen years of his life in a
village in the North of England, he made his way to London, an
intelligent and well-bred Quaker boy; and there he was so fortunate as
to be taken as an apprentice by Tompion, then the most celebrated
clock-maker in England, whose name is still to be seen upon ancient
watches and clocks. Tompion was a most exquisite mechanic, proud of his
work and jealous of his name. He is the Tompion who figured in
Farquhar's play of "The Inconstant;" and Prior mentions him in his
"Essay on Learning," where he says that Tompion on a watch or clock was
proof positive of its excellence. A person once brought him a watch to
repair, upon which his name had been fraudulently engraved. He took up a
hammer and smashed it, and then selecting one of his own watches, gave
it to the astonished customer, saying: "Sir, here is a watch of my
making."

Graham was worthy to be the apprentice of such a master, for he not only
showed intelligence, skill, and fidelity, but a happy turn for
invention. Tompion became warmly attached to him, treated him as a son,
gave him the full benefit of his skill and knowledge, took him into
partnership, and finally left him sole possessor of the business. For
nearly half a century George Graham, Clock-maker, was one of the best
known signs in Fleet Street, and the instruments made in his shop were
valued in all the principal countries of Europe. The great clock at
Greenwich Observatory,