his
countrymen accepted the dictatorship on the 5th of December 1830; on the
23rd of January 1831, however, he resigned in order to fight as a common
soldier. At Wavre (Feb. 19) and at Grochow (Feb. 20) he displayed all
his old bravery, but was so seriously wounded at the battle of Olszyna
that he had to be conveyed to Cracow, near which city he lived in
complete retirement till his death in 1854.

See Jozef Maczynski, _Life and Death of Joseph Chlopicki_ (Pol.)
(Cracow, 1858); Ignacy Pradzynski, _The Four Last Polish Commanders_
(Pol.) (Posen, 1865).

CHLORAL, or TRICHLORACETALDEHYDE, CCl3.CHO, a substance discovered by J.
von Liebig in 1832 (_Ann._, 1832, 1, p. 189) and further studied by
J.B.A. Dumas and Staedeler. It is a heavy, oily and colourless liquid,
of specific gravity 1.541 at 0 deg. C., and boiling-point 97.7 deg. C. It
has a greasy, somewhat bitter taste, and gives off a vapour at ordinary
temperature which has a pungent odour and an irritating effect on the
eyes. The word _chloral_ is derived from the first syllables of
_chlorine_ and _alcohol_, the names of the substances employed for its
preparation. Chloral is soluble in alcohol and ether, in less than its
own weight of water, and in four times its weight of chloroform; it
absorbs chlorine, and dissolves bromine, iodine, phosphorus and sulphur.
Chloral deliquesces in the air, and is converted by water into a
hydrate, with evolution of heat; it combines with alcohols and
mercaptans. An ammoniacal solution of silver nitrate is reduced by
chloral; and nascent hydrogen converts it into aldehyde. By means of
phosphorus pentachloride, chlorine can be substituted for the oxygen of
chloral, the body CCl3.CCl2H being produced; an analogous compound,
CCl3.C(C6H5)2H, is obtained by treating chloral with benzene and
sulphuric acid. With an alkali, chloral gives chloroform (q.v.) and a
formate; oxidizing agents give trichloracetic acid, CCl3.CO(OH). When
kept for some days, as also when placed in contact with sulphuric acid
or a very small quantity of water, chloral undergoes spontaneous change
into the polymeride _metachloral_ (C2Cl3OH)3, a white porcellaneous
body, slowly volatile in the air, and reconverted into chloral without
melting at 180 deg. C. Chloral unites directly with hydrocyanic acid to
form [beta]-trichloracetonitrile, CCl3.CH(OH)CN, and with hydroxylamine it
forms chlorglyoxime, C2H3ClN2O2.

Chloral is prepared by passing dry chlorin