CYC 
snannfecture has of late undergone very 
considerable improvement, by an inven- 
tion of Mr. Lucas of Sheffield, for which 
he has obtained a patent. The articles are 
cast of the most fusible pig-iron, and are 
afterwards converted into a state of steel 
by cementation. The pig-iron which only 
differs from steel in containing an excess 
of carbon, is stratified in close vessels, with 
some substance capable of furnishing oxy- 
gen, with which the carbon of the pig-iron 
combines, forming carbonic acid, which es- 
capes in the form of gas. See the article 
Steel. 
CUTTER, in naval affairs, a small vessel 
commonly navigated in the channels of Eng- 
land, furnished with one mast and a straight 
running bowsprit, or which can be run in 
on deck occasionally; except which, and 
the largeness of the sails, they are rigged 
much like sloops. 
CUTTLE FISH. See Sepia. 
CYANELLA, in botany, a genus of the 
Hexandria Monogynia class and order. 
Natural order of Coronari®. Asphodel!, 
Jussieu. Essential character: corolla six- 
petalled; the three lower petals hanging 
forwards; stamens lower declined, longer 
than the rest. There are three species, na- 
tives of the Cape. 
CYATHEA, in botany, a genus of the 
Cryptoganiia Tilices class and order. Fruc- 
tification in roundish scattered dots, seated 
on a columnar receptacle, within the calyx- 
like involucre which opens at top; there 
are about nine species. 
CYATHUS, in botany, a genus of the 
Cryptogamia Fungi: fungus campanulate 
or cylindrical, bearing lentiform capsules 
within. There are six species. 
CYCAS, in botany, a genus of the 
Dioecia Polyandria class and order. Natu- 
ral order of Palms. Filices, or Ferns, Jus- 
sieu. Essential character: male, ament- 
strobile form, with the scales covered every 
where beneath with pollen. Female, spa- 
dix sword-form; germ immersed into the 
comers of it solitary; style one; drupe 
with a woody nut. There are two species, 
viz. C. circinalis, broad-leaved cycas, and C. 
revoluta, narrow-leaved cycas. The first is 
a native of the Cape, the other of China, 
where it is cultivated for its beauty. 
CYCLAMEN, in botany, English cycla- 
men, or sow-bread, a genus of the Pentan- 
dria Monogynia class and order. Natural 
order of Preci®. Lysimachi®, Jussieu. 
Essential character : corolla rotate, reflex, 
with a very short tube and prominent throat ; 
CYC 
beriy covered with a capsule. According 
to Martyn there are five species. Linn®us- 
reckons two. Millar and Parkinson make 
eight and ten. The flowers are borne singly- 
on a naked stem, peduncle or scape, and 
ai-e nodding. The root is roundish, solid, 
and tuberous. Linn®us observes, that the 
several varieties connect the plants which 
have angular leaves with those which have 
round ones, so intimately that limits are 
assigned to them with difficulty. They are 
most of them natives of the South of Europe. 
CYCLAS, in botany, a genus of the 
Decandria Monogynia class and order.' 
Natural order of Lomentace®. Legumi- 
nos®, Jussieu. Essential character : calyx- 
four-parted, spreading, with a short timbi- 
nate tube ; corolla none ; filaments inserted 
into the neck of the calyx ; style flexuose ; 
legume roundish, winged, one-seeded. There 
are two species, viz. C. spicata, and C. aro- 
matica, both very tall trees, natives of tlie. 
great forests of Guiana, flowering in No- 
vember and December. 
CYCLIDIUM, in natural history, a ge- 
nus of Vermes Infusoria. Worm invisible 
to the naked eye, very simple, pellucid, 
flat, orbicular, or oval. There are seven 
species. C. buUa; orbicular, transparent; 
in infusions of hay; pellucid, white, with 
the edges a little darker ; motion slow and. 
circular. C. milium; elliptical, transpa- 
rent ; in vegetable infusions ; pellucid,- 
crystalline, membranaceous, with a line 
through the whole length. 
CYCLOID, in geometry, a curve of the 
transcendental kind, called also the trochoid. 
It is generated in the following manner : if 
the circle C D H (Plate III. Miscel. fig. 15.) 
roll on the given straight line A B, so that 
all the parts of the circumference be appli- 
ed to it one after another, the point C that 
touched the line A B in A, by a motion 
thus' compounded of a circular and recti- 
linear motion, will describe the curve 
A CEB, called the cycloid, the properties 
of which are these : 1. If on the axis E F 
be described the generating circle EGF 
meeting the ordinate C K in G, the ordi- 
nate will be equal to the sum of the arc 
E G and its right sine G K ; that is, C K 
will be equal to E G -f- G K. 2. The line 
CH parallel to the chord EG is a tangent 
to the cycloid in C. 3. The arch of the 
cycloid EL is double of the chord E M, of 
the corresponding arc of the generating cir- 
cle E M F : hence the semi-cycloid E L B 
is equal to twice the diameter of the gene- 
rating circle EF; and the whole cycloid' 
