CROTCHET (from the Fr. croche, a hook; whence also the Anglicized “crochet,” pronounced as in French, for the knitting-work done with a hook instead of on pins), properly a small hook, and so used of the hook-like setae or bristles found in certain worms which burrow in sand. In music, a “crotchet” is a note of half the value of a minim and double that of a quaver; it is marked by a round black head and a line without a tail or hook; the French croche is used of a “quaver” which has a tail, but in ancient music the semiminima, the modern crotchet, is marked by an open note with a hook. Derived either from an old French proverbial phrase, il a des crochues en teste, or from a meaning of twist or turn, as in the similar expression “crank,” comes the sense of a whim, fancy or perverse idea, seen also in the adjective “crotchety” of a fussy unreasonable person.
CROTONA, Croto or Croton (Gr. Κρότων, mod. Cotrone) a Greek town on the E. coast of the territory of the Bruttii (mod. Calabria), on a promontory 7 m. N.W. of the Lacinian promontory. It was founded by a colony of Achaeans led by Myscellus in 710 B.C. Its name was, according to the legend, that of a local prince who afforded hospitality to Heracles, but was accidentally killed by him and buried on the spot. Like Sybaris, it soon became a city of power and wealth. It was especially celebrated for its successes in the Olympic games from 588 B.C. onwards, Milo being the most famous of its athletes. Pythagoras established himself here between 540 and 530 B.C. and formed a society of 300 disciples (among whom was Milo), who acquired considerable influence with the supreme council of 1000 by which the city was ruled. In 510 B.C. Crotona was strong enough to defeat the Sybarites, with whom it had previously been on friendly terms, and raze their city to the ground. Shortly afterwards, however, an insurrection took place, by which the disciples of Pythagoras were driven out, and a democracy established. The victory of the Locrians and Phlegians over Crotona in 480 B.C. marked the beginning of its decline. It suffered after this from the attacks of Dionysius I., who became its master for twelve years, of the Bruttii, and of Agathocles, and even more from the invasion of Pyrrhus, after which in 277 the Romans obtained possession of it. Livy states that the walls had a length of 12 m. and that about half the area within them had at that time ceased to be inhabited. After the battle of Cannae Crotona revolted from Rome, and Hannibal made it his winter quarters for three years. It was made a colony by the Romans at the end of the war (194 B.C.). After that time but little is heard of it, though Petronius mentions the corrupt morals of its inhabitants; but it continues to be mentioned down to the Gothic wars. The importance of the city was mainly due to its harbour, which, though not a good one, was the only port between Tarentum and Rhegium. The original settlement occupied the hill above it (143 ft.) and later became the acropolis. Its healthy situation was famous in antiquity, and to this was ascribed its superiority in athletics; it was the seat also of a medical school which in the days of Herodotus was considered the first in Greece. Of the exact site of the ancient city and its remains practically nothing is known; a few fragments of the productions of its art preserved in private hands at Cotrone are described by F. von Duhn in Notizie degli scavi, 1897, 343 seq.
(T. As.)
CROTONIC ACID (C4H6O2). Three acids of this empirical formula are known, viz. crotonic acid, isocrotonic acid and methacrylic acid; the constitutional formulae are—
The isomerism of crotonic and isocrotonic acids is to be explained on the assumption of a different spatial arrangement of the atoms in the molecule (see [Stereochemistry]).
Crotonic acid, so named from the fact that it was erroneously supposed to be a saponification product of croton oil, may be prepared by the oxidation of croton-aldehyde, CH3·CH:CH·CHO, obtained by dehydrating aldol, or by treating acetylene successively with sulphuric acid and water; by boiling allyl cyanide with caustic potash; by the distillation of β-oxybutyric acid; by heating paraldehyde with malonic acid and acetic acid to 100° C. (T. Komnenos, Ann., 1883, 218, p. 149).
CH2(COOH)2 + CH3CHO → CH3CH:C(COOH)2 → CH3·CH:CH·COOH;