tial calculus enable us to calculate the speed, the change of
speed, the change of direction of motion (i. e. the curvature of the
path), and the effective force acting on the body. Conversely, given the
force at every point, and the initial position and velocity, the rules of
the integral calculus assist us in calculating the position and velocity
of the body at any future time. Expressed somewhat crudely, the
differential calculus has to do with the _differentials_ (increments or
decrements) of varying quantities; while the integral calculus is a
process of summation or _integration_ of these differentials.

CALCUTTA (900), on the left bank of the Hooghly, the largest and
westernmost branch of the Ganges delta, about 80 m. from the sea; is the
capital of Bengal and the Indian Empire, and the residence of the
Governor-General; the Government buildings, Bishop's College (now an
engineering school) High Court, town hall, bank, museum, university, St.
Paul's cathedral, and many other English Buildings have earned for it the
name "city of palaces"; but the native quarters, though being improved,
are still squalid, the houses of mud or bamboo; an esplanade, numerous
quays, an excellent water-supply, gas, and tramway services, add to the
amenities; there are extensive dockyards, warehouses, iron-works, timber
yards, and jute mills; extensive railway and steamboat communications
make it the chief emporium of commerce in Asia; ships of 5000 tons enter
the docks; founded in 1686, Calcutta was captured by Surajah Dowlah, and
the "Black Hole" massacre perpetrated in 1756; became the capital of
India in 1772, and has suffered frequently from cyclones; the population
are two-thirds Hindus, less than a third Mohammedan, and 41/2 per cent.
Christian.

CALDECOTT, RANDOLPH, artist, born in Chester; exercised his art
chiefly in book illustrations, which were full of life, and instinct with
a kindly, graceful humour; though professionally untrained, his abilities
as an artist were promptly and generously recognised by the Academy; he
suffered from ill-health, and died in Florida, whither he had gone to
recruit (1846-1886).

CALDER, SIR ROBERT, British naval officer; served bravely in several
naval engagements; was tried by court-martial, and reprimanded for not
following up a victory which he had gained, a sentence which was
afterwards found to be unjust; attained afterwards the rank of admiral
(1745-1818).

CALDERON DE LA BA