*70 
C U ? 
C U P 
C U R 
■species, small trees of the West Indies, which | 
possess no remarkable property. 
CUPEL, in metallurgy, a small vessel , ! 
which absorbs metallic bodies when changed j 
by lire into a fluid scoria ; but retains them j 
as long as they continue in their metallic 1 
state. One of the most proper materials for 
making a vessel of this kind is the ashes of 
animal bones ; there is scarcely any other 
substance which so strongly resists vehement 
lire, and which so readily imbibes metallic 
scoria;. See Chemistry. 
CO PELLA LION, the act of refining gold 
or silver by means of a cupel. For this pur- 
pose another vessel called a mullle is made 
use of, within which one or more cu;>els are 
placed. 1 he muffle is placed upon a grate 
in a proper furnace, with its mouth facing 
the door, ancl-as close to it as may be. The 
furnace being filled up with fuel, some light- 
ed charcoal is thrown on the top, and what 
fuel is afterwards necessary is supplied through 
a door above. The cupels are set in the 
muffle; and being gradually heated by the 
successive kindling of the fuel, they are kept 
red-hot for some time, that the moisture 
which they strongly retain may be com- 
pletely dissipated; for if any vapours should 
issue from them after the metal is put in, 
they would occasion it- to sputter, and a part 
of it to be thrown off in little drops. In the 
sides of the muffle are some perpendicular 
slits, with a knob over the top of each, to pre- 
vent any small pieces of coals or ashes from 
falling in. The door, or some apertures in it, 
being kept open, for the inspection of the 
cupels, fresh air enters into the muffle, and 
passes oil through these slits ; by laying some 
burning charcoal on an iron plate before the 
door, the air is heated before its admission ; 
and by removing the charcoal, or supplying j 
more, the heat in the cavity of the muffle I 
may be somewhat diminished or increased i 
move speedily than can be effected by sup- 
pressing or evening the fire in the furnace on 
the outside of the muffle. The renewal of 
the air also is necessary for promoting the 
scorification of the lead. See Chemistry. 
The cupel being of a full red heat, the lead, 
cast into a smooth bullet that it may not 
scratch or injure the surface, is laid lightly in 
the cavity ; it immediately melts, and then 
the gold or silver- to be’ cupelled is cau- 
tiously introduced, either by means of a small 
iron aule, or by wrapping them in paper, 
and dropping them on the lead with a pair 
of tongs. The quantity of lead should be at 
least three or four times that of the line 
metal; but when gold is very impure, it re- 
quires 10 or 12 times its quantity of lead for 
cupellation. It is reckoned that copper re- 
quires for its- scorification about 10 times its 
weight of lead; that when copper and gold 
are mixed in equal quantities, the copper 
is so much defended by the gold, as not to be 
separable with less than 20 times its weight of 
lead ; and that when copper is in very small 
proportion, as a_20th or 30th part of the gold 
or silver, upwards of 60 parts of lead are ne- 
cessary for one of the copper. The cupel 
must always weigh at least half as much as 
the lead and copper, for otherwise it will 
not be sufficient for receiving half thf? scoria ; 
there is little danger, however, of cupels be- 
ing made too small for the quantity of a gold 
assay. 
6 
The mixture being brought into thin fu- 
sion, the heat is to be regulated according to 
the appearances, and in this consists the 
principal nicety of the operation. If a va- 
rious-coloured skin rises at the top, which 
liquefying, runs off to the sides, and is there 
absoi bed by the cupel, visibly staining die 
parts it enters ; if a fresh scoria continually 
succeeds, and is absorbed nearly as fast as it 
is formed, only a line circle of it remaining 
round the edge of the metal'; if the lead ap- 
pears in gentle motion, and throws up a fume 
a little way from the surface ; then the lire 
is of the proper degree, and the process goes 
on successfully 
Such a fiery brightness of the cupel as pre- 
vents its colour from being distinguished, and 
the fumes of the lead rising up almost to 
the arch of the muffle, are marks of too 
strong a heat : though it must be observed, 
that the elevation of the fumes is not always 
iu proportion to the degree of heat; for if the 
heat greatly exceeds the due limits, both the 
fumes and ebullition will entirely cease. In 
these circumstances the lire must necessarily 
be diminished ; for while the lead boils and 
smokes vehemently, its fumes are apt to 
carry 'off some part of the gold ; the cupel is 
liable to crack, from the hasty absorption of 
the scoria ; and part of the gold and silver is 
divided into globules, which lying discon- 
tinued on the cupel after the process is finish- 
ed, cannot easily be collected ; if there is no 
ebullition or fumes, the scorification does not 
appear to go on. Too weak a heat is known 
by the dull redness of the cupel, by the fume 
not rising from the surface of the lead, and 
the scoria appearing like bright drops in lan- 
guid mot ion, or accumulated, or growing con- 
sistent all over the metal. The form of the 
surface affords also an useful mark of the degree 
of heat; the stronger the lire the more convex 
is the surface, and the weaker .the more flat; 
in this point, however, regard must be had to 
the quantity of metal ; a large quantity being 
always Hatter than a small one in an equal 
lire. 
Towards the end of the process, the fire 
must be increased ; for the greatest part of 
the fusible metal lead being now worked off, 
the gold and silver will not continue melted 
in the heat that was sufficient before. As 
the last remains of the lead are separating, 
the rainbow colours on the surface become 
more vivid, and variously intersect one an- 
other with quick motions. Soon after, dis- 
appearing all at once, a sudden luminous 
brightness ot the button of gold and silver 
shows the process to be finished. The cupel 
is then drawn forwards towards the mouth 
ot the muffle; anti the button, as soon as 
grown fully solid* taken out. 
CUPOLA, in architecture, a spherical 
vault; or qhe round top of the dome of a 
church, in form of a cup inverted. 
CUPPING, in surgery, the operation of 
applying cupping-glasses for the discharged 
blood, and other humours, by the skin. ” See 
Surgery. 
CUPRESSUS, the cypress-tree, a genus 
of the monadelphia order, in the monoecia 
class of plants, and in the natural method 
ranking under the 51st order, conifers. The 
male calyx is -a scale of the catkin; there is 
no corolla ; the anthers are four, sessile, and 
without filaments. The calyx of the female 
is a scale of the stroffllus,. and uniflorous ; in- 
stead of the stylus there are hollow dots ; the 
fruit is an angulated nut. There are seven- 
species; the most remarkable are the follow- 
ing: J. The sempervirens, or evergreen, 
with an upright straight stem, closely branch- 
ing all round, almost from the bottom- Ho- 
wards, into numerous quadrangular branches, 
rising in the different varieties from 15 to 40 
or 50 feet in height, with small, narrow, erect 
evergreen leaves, placed imbricatim, and 
flowers and fruit from the sides of the 
brandies. 2. The thyoides, or evergreen 
American cypress, commonly called white 
cedar, has an upright stem branching out into 
numerous two-edged branches, rising 20 or 
30 feet high, ornamented with the Hat ever- 
green leaves, imbricated like the arbor vine, 
aud small blue cones, the size of juniper-ber- 
ries. 3. The disticlia, or deciduous American 
cypress, has an erect trunk, retaining a large 
bulk, branching wide and regular; grows 50 
or 60 feet high, with small spreading deci- 
duous leaves, arranged distichous, or aloim 
two sides of the branches. All these species 
are raised from seeds, and will sometimes 
also grow from cuttings ; but those raised 
from seeds prove the handsomest plants. 
The seeds are procured in their cones from 
the seedsmen, and by exposing them toa mo- 
derate heat, they readily open! and discharge 
their seeds freely. The season for sowing 
them is any time in March ; and they grow 
freely on a bed of common light earth, espe- 
cially the first and third species. 
The wood of the first species is said to re- 
sist worms, moths, and putrefaction, and to 
last many centuries. The coffins in which 
the Athenians were used to bury their he- 
roes, were made, says Thucydides, of this 
wood ; as were likewise the chests containing 
the Egyptian mummies. The doors of St! 
Peter’s church at Home were originally of 
the same materials; These, after lasting up- 
wards of 600 years, at the end of which they 
did not discover the smallest tendency to 
decay, were removed by order of pope Eu- 
genius IV 7 . and gates of brass substituted in 
their place. The same tree has been ex- 
tolled as a remedy in pulmonic diseases, from 
its supposed property of meliorating the air 
by its balsamic exhalations; upon which ac- 
count many antient physicians of the eastern 
countries used to send their patients to the 
island of Candia, where these trees grew in 
great abundance. In that island, says Mil- 
ler, the cypress-trees w'ere so lucrative a 
commodity, that the plantations were called 
dos filia;; the telling of one of them being 
reckoned a daughter’s portion. Cypress, 
says Mr. Pococke, is the only tree that 
grows towards the top of mount Lebanon, 
and being nipped by the cold, grows like a 
small oak. Noah’s ark is Commonly suppos- 
ed to have been made of this kind of wood. 
CURATE, is he who represents the in- 
cumbent of a church, parson, or vicar, and 
performs divine service in his stead ; and in 
case of pluralities of livings, or where aclergv - 
man is old and infirm, it is requisite there 
should be a curate to perforin the cure of the 
church. He is to be licensed and admitted 
by the bishop of the diocese, or by an ordi- 
nary having episcopal jurisdiction : and 
when a curate has the approbation of the 
bishop, he usually appoints the salary too ; 
and in such case, if he is not paid, the curate 
has a proper remedy in the ecclesiatical 
