ch, with his _Introduction to the Study of Physics_
(c. 1756), his _Enquiry into the Principles of Vital Motion_ (1766), and
his _Reflections_ (c. 1770), mark him as the first of American
materialists and one of the ablest material philosophers of his day. I.
Woodbridge Riley, in _American Philosophy_ (New York, 1907), made the
first critical study of Colden's philosophy, and said of it that it
combined "Newtonian mechanics with the ancient hylozoistic doctrine ..."
and "ultimately reached a kind of dynamic panpsychism, substance being
conceived as a self-acting and universally diffused principle, whose
essence is power and force."

See Alice M. Keys, _Cadwallader Colden, A Representative 18th Century
Official_ (New York, 1906), a Columbia University doctoral
dissertation; J. G. Mumford, _Narrative of Medicine in America_ (New
York, 1903); and Asa Gray, "Selections from the Scientific
Correspondence of Cadwallader Colden" in _American Journal of
Science_, vol. 44, 1843.

His grandson, CADWALLADER DAVID COLDEN (1769-1834), lawyer and
politician, was educated in London, but returned in 1785 to New York,
where he attained great distinction at the bar. He was a colonel of
volunteers during the war of 1812, and from 1818 to 1821 was the
successor of Jacob Radcliff as mayor of New York City. He was a member
of the state assembly (1818) and the state senate (1825-1827), and did
much to secure the construction of the Erie Canal and the organization
of the state public school system; and in 1821-1823 he was a
representative in Congress. He wrote a _Life of Robert Fulton_ (1817)
and a _Memoir of the Celebration of the Completion of the New York
Canals_ (1825).

COLD HARBOR, OLD and NEW, two localities in Hanover county, Virginia,
U.S.A., 10 m. N.E. of Richmond. They were the scenes of a succession of
battles, on May 31-June 12, 1864, between the Union forces under command
of General U. S. Grant and the Confederates under General R. E. Lee, who
held a strongly entrenched line at New Cold Harbor. The main Union
attack on June 3 was delivered by the II. (Hancock), VI. (Wright), and
XVIII. (W. F. Smith) corps, and was brought to a standstill in eight
minutes. An order from army headquarters to renew the attack was ignored
by the officers and men at the front, who realized fully the strength of
the hostile position. These troops lost as many as 5,000 men in an
hour's fighting, the greater part in the few minutes o