Page:The New International Encyclopædia 1st ed. v. 05.djvu/63

* CLOCK. 184t! his system was in use between Glasgow and Edinburgh. Pnevm.tic Clocks. A system of synchronous clocks which are connected with the central controlling oUick by compressed air instead of electricity is called piunimatie. The clockwork in the City Hall at Philadelphia, descril)ed above, is of this type. The movement of the cen- tral clock compresses air in the connecting tubes, and causes a bellows to expand at eacli dial, tlius moving the hands. A.STR0N0M1CAL Cx-OCKS. An astronomical clock is one built with the simplest and most accurate mechanism possible, and with every possible protection against outside disturbances, so that its movements will be sufficiently ac- curate for astronomical calculations. One of the most important considerations for an accurate timekeeper of this class is that it should be maintained at a constant tempei'aturc. and often in astronomical observatories, rooms are special- ly constructed for tliis particular purpose. It will l>e noticed, from the accompanying cut of the astronomical clock in the City Hall at Philadel- phia, that the dial has three circles — the minute- circle above the centre, the twelve-hour circle be- neath the centre, and the hour-circle upon the circumference of the dial. A clock regulated to keep sidereal time is sometimes called an astro- nomical clock, as is also a clock having a dial on ■which the movements of the heavenly bodies are slioMi. Clocks and Watches Exported from the United St.atks (From the Statistical .Abstract of the United States for 1900) YEAR "Watches Clocks Total 1891 $275,707 208,743 241,758 383,279 357,329 630,980 801,491 771,912 819,810 787,620 $1,304,457 1,020,873 962,423 919,534 846,676 929,395 968,911 955.557 1,043.621 1,190,074 $1,580,146 1892 1.229,616 1893 1,204.181 1894 1,302,813 1895 1,204,005 1696 1,460,375 1897 1,770,402 1898 1,727,469 1899.., 1,863.431 1900"'":.; 1,977,694 Clock-Makufacture in the United States. American clocks were first manufactured in Con- necticut, about 1800, by Eli Terry. His clocks soon became popular, and he continued in busi- ness until his death, when his sons succeeded him, under the name of the 'Terry ilanufac- furing Company.' Many neighboring establish- ments were soon engaged in clock-manufacture, and Connecticut is still the centre of the indus- try in the United States. According to the census of 1850, there were 1436 clock-factories and 2001 watch-factories in the United States. At first the movements were constructed of wood, and in the better clocks the pendulum was of wood overlaid with gold-leaf. In 1814 Terry invented the 'short-shelf clock,' which rapidl.y displaced the long or hanging clocks previously made. Brass-wheel clocks were not made in the United States until 18.37. American manu- facturers introduced the system of cutting out the parts from sheet brass with a die, instead of casting them — a method which at once in- sured greater accuracy as well as cheapness in tlje product. The adoption of the die and of other forms of automatic machinery in the manu- facture of clocks has now been carried to such an extent that nothing is left for the skilled 47 CLODIUS PULCHEB. hand-laborer but the collocation of the parts. Coiled springs, instead of pendulums, had been used in European clocks fur two bundled years before their use was introduced into American factories ; but they were placed only in tile most expensive clocks: the invention of a reliable but cheap steel spring, which could be placed in the least expensive clocks, is due to American enter- prise, and its introduction has revolutionized the dock-making imlustry. The >mall .-•priiig chicks can be nianiifacturcd and sold for less than one dollar, and are very popular. BiBLiOGRAi'iiY. The following are general works on horology: Saunier, Treolisc on Modern Horoloyi/ In Theory and I'riietiee, trans, from the French, by Julien Tujipier and Edward Kigg (London, 1897); Kendall, llislorij of Watches and Other Timekeepers (London, 18U7); Grin- thorge, Kudimentanj Treatise on Clorks, Watches, and Bells (London, 1883). In the Journal of the Society of Arts (London) for March 7, 18!)0, is an interesting article by Julien Tuplin, on "Eecent Progress in British Watch and Clock Making." The Supplement of the tieienti/ic American for September 19, 1896, contains an article translated from the French on ''Clocks Provided with Automatons." The Philadelphia City-Hall Clock is dcscrilied in the Journal of the Franklin Institute (Phila- delphia) for February, 1901. The Etectriciati (London) for December 2'2, 1899, contains an article by F. Hope Jones, on "The Electric Time-Service." See Watch : Time-Signals ; Time. SrANOARn. CLOCK BELL-METAL. An alloy used for the making of bells in clocks, which may have the following composition: 72 parts copper. 26. .56 parts tin, and 1.44 parts silver. The silver is added to give sweetness to the tone. In some cases, bismuth and antimony are added in small quantities; but while they are said to produce a better tone, they make the alloy more brittle. CLODIA. The infamous sister of Clodius, and wife of Quintus Motellus Celer, whom she is supposed to have poisoned. She is identified with the Lesbia to whom Catullus addressed his love-poems. Her younger sister Clodia mar- ried Lucullus, but was put away on account of her conduct. CLODIUS PULCHER, klo'dl-iis pulTver, Ptblus. a Roman demagogue. He appears in history, in B.C. 70, serving under Lucullus in Asia. In 69 he inipeaclied Catiline for ex- tortion in Africa; but Catiline bribed his ac- cuser and escaped. Clodius appears to have been avaricious and unscrupuhms. Near the close of the year 62 he was said to have had an intrigue with Poni])eia, wife of Julius Cicsar. on the occasion of the celebration of the rites of the Bona Dea in Cajsar's house. Clodius was tried for violation of the sacred mysteries, but was acquitted, it was charged, because he had bribed the judge. He was elected tribune in 59, and one of his first acts was to exile Cicero, who had refused to defend him in the trial for sacrilege: but the great orator was soon afterwards recalled, in spite of Clodius's op- position. He went on from bad to worse, gath- ering around him the worst elements of the people, until he became a candidate for the pretorship (B.C. 53) in opposition to Mila Both candidates worked with reckless energy.