CYC 2 



gen, by the action of hot water, which 

 converts that substance into hydrochloric 

 acid and cyanic acid. By evaporation 

 the hydrochloric acid is driven off, and 

 the cyanic acid is deposited in white 

 rhomboidal crystals. It is a compound of 

 one atom of cyanogen and two of oxygen. 



CY'ANIDE, j a combination formed by 



CY'AXODIDE, I cyanogen and a great 

 variety of bases, and exceedingly analo- 

 gous to the chlorides. The term cyanwet 

 is less objectionable. 



CY'AXITE, from xvotvo; , blue. 1. A mi- 

 neral of a blue or bluish-green colour, 

 which occurs regularly crystallised, and 

 also massive and disseminated. Consti- 

 tuents, 64 alumina, 34 silica, with some 



lime and oxide of iron. 2. A salt 



formed by the union of the cyanous acid 

 with a base, as the cyanite of baryta. 



CS'AXOGKX, called also prussine ; a co- 

 lourless gaseous compound discovered in 

 1815 by Gay-Lussac, and termed cyanogen 

 from xuotvof, blue, and ytwat,a>, to gene- 

 rate, in consequence of its being essen- 

 tial to the formation of Prussian blue. It 

 is obtained from dry cyanuret of mercury. 



CYANOM'ETER, Gr., from xvixvos, blue, 

 and u,irfs, measure. An instrument 

 contrived by Saussure for determining the 

 deepness of the tint of the atmosphere. 



CYA'XOUS ACID, an acid composed of 

 one atom of cyanogen and one atom of 

 oxygen. It is obtained only in solution, 

 and is little known. 



CTAN'L-RET, the same with cyanide (q. v.). 



CYAN'CRIC ACID, an acid that may be 

 obtained from urea. It is composed of 

 carbon, 6 ; nitrogen, 3 ; hydrogen, 3 ; and 

 oxygen, 6 ; condensed into one volume. 



CY'CAS, the sago-plant ; a genus of two 

 species, found in India and Japan. Diae- 

 ciaPolyandria (see SAGO). Named from 

 the xuxot.; of Theophrastus, a palm which 

 was said to grow in Ethiopia. 



CYCLA'MEN, the Sow-bread; a genus of 

 perennial plants. Pentandria Monogy- 

 nia. Name from xux\;, circular, either 

 on account of the round form of the leaves 

 or of the roots. 



'VCLE, from xvxKof , a circle ; a period 

 01 numbers which regularly proceed from 

 first to last, and then return to the first 

 in a perpetual circle, as, (1.) The C. of 

 the moon, called also the Metonlc cycle, 

 from its inventor Meton, and the golden 

 number; this is a period of 19 years, 

 which being completed, the new and 

 full moons return to the same days of 

 the month ; (2.) The C. of the tvn is a 

 period of 28 years, which being elapsed, 

 the dominical or Sunday letters return to 

 their former place and proceed in the 

 same order as before, according to the 

 Julian calendar; (3.) The C. of Indiction \ 



) C YL 



is a period of 15 years, at the end of 

 which the Roman emperors imposed an 

 extraordinary tav to pay the soldiers who 

 were obliged to serve in the army for 

 that time and no longer. 



CT'CLIC CHORUS, those who performed 

 the songs and dances of the dithyrambic 

 odes at Athens. 



CY'CLIC POETS, a succession of epic poets 

 who followed Homer. 



CT'CLOORAPH, from xvxho;, a circle, and 

 y^attfiu, to describe, an instrument for de- 

 scribing the arcs of circles. 



CT'CLOID, from xvxXo;, a circle, and 

 iTfof , form ; a transcendental curve gene- 

 rated by the revolution of a circle along a 

 straight line, called also a trochoid. If 

 we conceive the circle a c b x to roll along 

 the line AB, the point a being first at A, 

 and ending at the point B, this point a 

 will describe or pass through the curved, 

 line AaB, which curve line is the cycloid. 



Properties, the line AB = the cir. of the 

 circle acbx, the arc c=the right line 

 cd; the portion of the cycloid ad = 

 double the chord a c, and the area of the 

 whole cycloidal space A B a= thrice that 

 of the generating circle. 



CYCLOPZ'AN, pertaining to the Cyclops; 

 vast ; as C. buildings, which are formed of 

 huge blocks of stone piled upon each, and 

 constituting walls without cement. 



CYCLOPE'DIA, more correctly encyclope- 

 dia ; a work containing accounts of the 

 principal subjects in one or all depart- 

 ments of learning, art, or science. 



CYCLOP'TERCS, a genus of fishes ; order 

 Malacopterygii subrachiati ; family Disco- 

 boli. Name from xvXot, a circle, and 

 ;rs, a fin; the genus being marked by 

 the ventrals being suspended round the 

 pelvis, forming an oval and concave disc, 

 used by the fish as a sucker to attach 

 itself to rocks. Species, the Lumpsucker 

 (C. Zumpiu, Lin.) 



CTCLOS'TOMA, a genus of air-breathing 

 gastropods or snails. 



CYG'NUS (Latin), a swan; a constella- 

 tion bounded on the north by Draco, 

 east by Lacerta and Pegasus, south by 

 Vulpecula et Anser, and west by Lyra. 

 It contains 81 stars, the most brilliant of 

 which is Deneb. There are several fables 

 about the origin of this name. 



CYL'INDER, from cylindrus 

 from xuXiv'bca, to roll), a solid having a 

 circular base, and which base may oe 

 considered as carried upwards in a 

 straight line, and continuing the ciicle 



