CAL 
has a fine gloss, and is chequered in the warp, 
whence the checks appear only on the right 
side. Some calamancos are quite plain, 
others have broad stripes adorned with flowers, 
some with plain broad stripes, some with 
Harrow stripes, and others watered. 
CA LAMINAR IS, or Lapis C’alami- 
naris, in natural history, an ore of zinc, of a 
spungy substance, ami a lax and cavernous 
texture, yet considerably heavy. See Zinc. 
CALAMUS, a genus of the monogynia 
order, and hexandria class of plants ; and in 
the natural method ranking under the 5th 
order, tripetaloideaj. The calyx is liexa- 
phyllous, there is no corolla, the fruit is a dry 
monospermous berry, imbricated backwards. 
There is but one species, viz. 
Calamus rotang. The stem is without 
branches, has a crown at top, and is every 
where beset with straight spines. This is the 
true Indian cane, which is not apparently such 
on the outside ; but the external bark being 
taken off discovers the smooth stick, which has 
no marks of spine on the inner bark ; and is 
exactly like those which the Dutch sell to us, 
keeping this matter very secret, lest travellers 
going by should lake as many canes out of the 
woods as they please. Sumatra is said to be the 
place where most of these sticks grow. Such 
are to be chosen as are of proper growth, be- 
tween two joints, suitable to the fashionable 
length of canes as they were then used ; but 
such are scarce. The calamus rotang is one 
of several plants from which the drug called 
dragon’s blood is obtained. See Plate Nat.. 
Hist. fig. 72. 
Calamus aromaticus. See Acorus. 
CALATOR. in antiquity, was a public 
servant, and a freeman, such as a bailiff or 
crier, or summoner, to summon courts, sy- 
nods, and other public assemblies. 
CALATRAVA, knights of, a military 
order in Spain, instituted under Sancho III. 
king of Castile, upon the following occasion. 
When that prince took the strong fort of 
Calatrava from the Moors of Andalusia, he 
gave it to the Templars ; who, wanting cou- 
rage to defend it, returned it to him again. 
Then don Raymond, of the order of the 
Cistercians, accompanied with several per- 
sons of quality, made an oiler to defend the 
place, which the king thereupon delivered up 
to them, and instituted that order. 
CALCANEUM,or os calcis. See Ana- 
tomy. 
CALCINATION, in chemistry, such a 
management ofbodies by fire as renders them 
reducible to a calx or cinder. 
As most metals were reducible to this 
form, the term calces of metals was long ap- 
propriated to them; but in science the term is 
supplanted by the characteristic appellation 
of oxide, which expresses the peculiar 
change that occurs in calcining metallic bo- 
dies by the absorption of oxygen. Calcina- 
tion and oxidation are not strictly synony- 
mous, even when applied to metals, since 
the true sense of the former implies the 
agency of fire, but the metals may be oxi- 
dated by the action of the acids as well as by 
heat and air. 
CALCULI, Biliary, are hard bodies 
sometimes formed in the gall-bladder, or in 
the duct through which the bile passes into 
the intestinal canal, and stop up the passage 
altogether. They naturally drew the atten- 
tion of physicians, because it w r as soon ascer- 
C A L 
tained that they occasioned the disease called 
jaundice. Accordingly they were examined 
and described by different chemists, and the 
facts ascertained’ before 1764 were collected 
by Haller in the sixth volume of his Physio- 
logy. Since that period, a treatise has been 
published on them by Yicq d’Azyr; and se- 
veral new facts have been discovered by 
Poulletier de la Sale, Fourcroy, Gren, and 
Saunders. 
Such of the biliary calculi as have been 
hitherto examined with attention may be ar- 
ranged under four classes. 
1. The first kind. comprehends those w hich 
have a white colour, and a crystallized, shin- 
ing, lamellated structure. 
2. The second is brown-coloured, and lias 
the appearance of inspissated bile. 
3. The third class comprehends those cal- 
culi which are composed of a mixture of the 
substances which constitute the two last. 
4. The fourth comprehends those gall- 
stones which do not tiame, but gradually 
waste away at a red heat. 
Let us take a view of each of these classes 
of biliary calculi. 
1. The first species of biliary calculi w r as 
pointed out for the first time by Haller, in a 
dissertation published in 1749. Walther after- 
wards added several new facts ; and at last it 
was accurately described by Yicq d’Azyr. 
It is almost always of an oval shape, some- 
times as large as a pigeon’s egg, but com- 
monly about the size of a sparrow’s ; and for 
the most part only one calculus (when of this 
species) is found in the gall-bladder at a time. 
It lias a white colour, and when broken pre- 
sents crystalline plates or striae, brilliant and 
w hite like mica, and having, a soft greasy feel. 
Sometimes its colour is yellow 7 or greenish; 
and it has constantly a nucleus of inspissated 
bile. Its specific gravity is inferior to that 
of w’ater. Gren found the specific gravity of 
one 0.803. 
When exposed to a heat considerably 
greater than that of boiling water, this crys- 
tallized calculus softens and melts, and crys- 
tallizes again when the temperature is lower- 
ed. It is altogether insoluble in water ; but 
hot alcohol dissolves it with facility. Alco- 
hol, of the temperature of 167°, dissolves 
of its weight of this substance; but alcohol, 
at the temperature of 60°, scarcely dissolves 
any of it. As the alcohol cools, the matter 
is deposited in brilliant plates resembling 
talc, or boracic acid. It is soluble in oil of 
turpentine. When melted it has the appear- 
ance of oil, and exhales the odour of melted 
wax : when suddenly heated it evaporates 
altogether in a thick smoke. It is soluble in 
pure alkalies, and the solution lias all the pro- 
perties of a soap. Nitric acid also dissolves 
it; but it is precipitated unaltered by water. 
This matter, which is evidently the same 
with the crystals which Cadet obtained from 
bile, and w hich he considered as analogous to 
sugar of milk, has a strong resemblance to 
spermaceti. 1 .ike that substance, it is of an 
oily nature, and inflammable; but it differs 
from it in a variety of particulars. 
Since it is contained in bile, it is not diffi- 
cult to see how it may crystallize in the gall- 
bladder if it happens to be more abundant 
than usual; and the consequence must be a 
gall-stone of this species. Fourcroy found a 
quantity of the same substance in the dried 
human liver. 
CAL 285 
2. The second species of biliary calculus is 
of a round or polygonal shape, often of a 
grey colour externally, and brown within. 
It is formed of concentric layers of a mat’ r 
which seems to be inspissated bile ; and • - 
is usually a nucleus of the white cr 
matter at the centre. For the mow part W- c 
are many of this species of caiem w 
gall-bladder together ; indeed it is e • wy 
filled with them. The calculi belonging to 
this species are often light and 
of a brownish-red colour. The gail-btoims 
oxen, used by painters, belor l> tin- - 
3. The third species ot calculi eve me 
numerous of all. Their colour is cm a ri>-. , j 
brown or green ; and when broken a ran' her 
of spermaceti crystals are observable, mix- .'. 
with the inspissated bile. 
The calculi belonging to these three spe- 
cies are soluble in alkalies, in soap ley n in 
alcohol, and in oils. 
4. Concerning the fourth species of gall- 
stone, very little is known with accunmy. 
Dr. Saunders tells us that he has met varii 
some gall-stones insoluble both, in alcohol 
and oil of turpentine; some of which do not 
flame, but become red, and consume to an 
ash like a charcoal. Haller quotes several 
examples of similar calculi. 
Gall-stones often occur in the inferior ani- 
mals, particularly in cows and hogs; but the 
biliary concretions of these animals have not 
hitherto been examined with much attention. 
Calculi, urinary. It is well known that 
concretions not unfrequently form in die 
bladder, or the other urinary organs, and oc- 
casion one of the most dismal diseases to 
w hich the human species is liable. 
These concretions were distinguished by 
the name of calculi, from a supposition that 
they are of a stony nature.' They have long- 
attracted the attention of chemists and phy- 
sicians. Boyle extracted from calculi, by 
distillation, oil, and a quantity of volatile salts. 
Boerhaave supposed them compounds of oil 
and volatile salts. Slare attempted a chemical 
analysis of them. Hales extracted from them 
a prodigious quantity of air. He gave them 
the name of animal tartar, pointed out se- 
veral circumstances in which they resemble 
common tartar, and made many experiments 
to find a solvent of them. Drs. Whytt and 
Alston pointed out alkalies as solvents of cal- 
culi. It was an attempt to discover a more 
perfect solvent that induced Dr. Black to 
make those experiments, which terminated in 
the discovery of the nature of the alkaline 
carbonates. 
Such was the state of the chemical analysis 
of calculus, when, in 1776, Scheele published 
a dissertation on the subject in the Stock- 
holm Transactions, which was succeeded by 
some remarks ot Mr. Bergman. These illus- 
trious chemists completely removed the un- 
certainty which had hitherto hung over the 
subject, and ascertained the nature of the 
calculi which they examined. Since that 
time considerable additional light has been 
thrown upon the nature of these concretions 
by the labours of Austin, Walther, Bn: ■ n;i- 
telli, Pearson, Ac. But the most important 
additions to our knowledge of calculi were 
made by Dr. Wollaston. That ingenious 
chemist distinguished them into species, and 
ascertained the composition of each, pointing 
out several new constituents which had not 
been suspected before. 
