ustrating
the early history of man, now in the British Museum. He travelled in
Norway, Sweden, Denmark, Mexico, British Columbia and other countries;
but in 1858 came the opportunity which brought him fame. It was in that
year that the discoveries by Boucher de Perthes of flint-implements in
France and England were first held to have clearly proved the great
antiquity of man. Christy joined the Geological Society, and in company
with his friend Edouard Lartet explored the caves in the valley of the
Vezere, a tributary of the Dordogne in the south of France. To his task
Christy devoted money and time ungrudgingly, and an account of the
explorations appeared in _Comptes rendus_ (Feb. 29th, 1864) and
_Transactions of the Ethnological Society of London_ (June 21st, 1864).
He died, however, on the 4th of May 1865, of inflammation of the lungs
supervening on a severe cold contracted during excavation work at La
Palisse, leaving a half-finished book, entitled _Reliquiae Aquitanicae,
being contributions to the Archaeology and Palaeontology of Perigord and
the adjacent provinces of Southern France_; this was issued in parts and
completed at the expense of Christy's executors, first by Lartet and,
after his death in 1870, by Professor Rupert Jones. By his will Christy
bequeathed his magnificent archaeological collection to the nation. In
1884 it found a home in the British Museum. Christy took an earnest part
in many philanthropic movements of his time, especially identifying
himself with the efforts to relieve the sufferers from the Irish famine
of 1847.

CHROMATIC (Gr. [Greek: chromatikos], coloured, from [Greek: chroma],
colour), a term meaning "coloured," chiefly used in science,
particularly in the expression "chromatic aberration" or "dispersion"
(see ABERRATION). In Greek music [Greek: chromatike mousike] was one of
three divisions--diatonic, chromatic and enharmonic--of the tetrachord.
Like the Latin _color_, [Greek: chroma] was often used of ornaments and
embellishments, and particularly of the modification of the three
_genera_ of the tetrachord. The chromatic, being subject to three such
modifications, was regarded as particularly "coloured." To the Greeks
chromatic music was sweet and plaintive. From a supposed resemblance to
the notes of the chromatic tetrachord, the term is applied to a
succession of notes outside the diatonic scale, and marked by
accidentals. A "chromatic scale" is thus a series of semi-tones