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may easily be inferred from what we have said 
respecting the proper field culture. 
Caraway seeds have a pleasant aromatic odour, 
and a sweetish, warm, pungent taste; they yield 
by distillation a volatile oil, which contains the 
whole of their aroma and active properties ; they 
are extensively used by confectioners, in the ma- 
nufacture of comfits, and by pastry-bakers in the 
preparation of fancy-breads; and they are em- 
ployed, in medicine, to give warmth to cold pur- 
gatives, to dispel hysteria and flatulent colic, and 
to operate as a carminative and an axillary tonic. 
Not fewer than ten different preparations of them 
are ordered by the pharmacopeias. The seeds, 
especially in a state of powder, are much used in 
veterinary practice, as acarminative, a cordial, and 
an aromatic. They are, in any case of veterinary 
practice, second only to ginger as an aromatic ; 
and in some cases, they are greatly preferable. 
But when caraway powder is purchased, care- 
ful examination of it ought to be made, lest it 
should prove to be only the worthless residuum of 
the still— Agricultural Survey of Hssex.—Rham’s 
Dictionary of the Farm.—Miller’s Dictionary.— 
Mortimer’s Husbandry—Thomson’s London Dis- 
pensatory.—Loudon’s Hortus Britannicus.—Clater’s 
| Cattle Doctor.—Dunglisson’s Materia Medica. 
CARBON. Charcoal, as we are familiar with 
it in common life, contains hydrogen, and saline, 
and metallic substances. Accordingly, it became 
necessary to introduce a peculiar term for its 
pure base, and the one adopted by chemists was 
carbon. This element, besides forming the in- 
flammable matter of charcoal, exists largely in 
animal substances, and is extensively distributed 
in the mineral kingdom. 
The only body in which carbon has been found 
to exist in a state of absolute purity,,is the dia- 
mond, This precious stone has always been 
esteemed as the most valuable of the gems—a 
superiority which it owes to its hardness, lustre, 
and high refractive power. Diamonds are brought 
from India and from Brazil. Those of India, 
which have been the longest known, are princi- 
pally found in the kingdoms of Golconda and of 
Visiapour. Those of Brazil, discovered at the 
commencement of the 17th century, belong to 
the district of Serro-do-Frio. The situations in 
which they occur are such as to favour the idea 
of their recent formation ; since they exist dis- 
‘seminated through a loose, ferruginous sand- 
stone, or quite detached in a sandy soil; and, in 
both cases, are situated at no great depth below 
the surface. In Brazil, the conglomerate in which 
they exist is called cascalho; from which they 
are extracted by washing, in the same manner as 
gold. The diamond uniformly occurs crystallized, 
and presents a great variety of forms; all of 
which yield readily to mechanical division paral- 
lel to all the planes of the regular octohedron, 
which, therefore, is the form of the primary crys- 
tal, and under which figure it is sometimes found 
CARBON, 
quently curved, so as to communicate to them a 
rounded appearance. They are commonly lim- 
pid; and are either colourless, or of a yellowish, 
bluish, yellowish-brown, black-brown, Prussian 
blue or rose-red colour. Specific gravity, 3:5. 
Its hardness is extreme; so that it can be worn 
down only by rubbing one diamond against ano- 
ther, and is polished only by the finer diamond 
powder. The weight, and, consequently, the 
value of diamonds, are estimated in carats, one 
of which is equal to four grains; and the price 
of one diamond compared with that of another 
of equal colour, transparency, and purity, is as 
the squares of the respective weights. The aver- 
age price of rough diamonds, that are worth 
working, is about £2 for the first carat. The 
value of a cut diamond is equal to that of a 
rough diamond of double weight, exclusive of 
the price of workmanship; and the whole cost of 
a wrought diamond of 
1 carat may be about : £8 
Qicarats is 22 K £8 = 32 
3 do. Ista. 3210058! = 72 
4 do. 1Sjay p42) GeO 126 
100 do. is 1002 x §& = 80,000 
This rule, however, is not extended to diamonds 
of more than 20 carats. The larger ones are dis- 
posed of at prices inferior to their value by that | 
computation. The snow-white diamond is most 
prized by the jeweller. When transparent, and 
free from cracks, it is said to be of the first water. 
—The following are some of the most extraordi- 
nary diamonds known :—one in the possession of 
the Rajah of Mattan, in the island of Borneo, 
where it was found about a century ago: it is 
shaped like an egg, and is of the finest water : 
its weight is 367 carats, or 2 oz. 169 grs. Troy. 
Another is the celebrated Pitt diamond, now 
among the crown jewels of France, weighing 136 
carats; another in the sceptre of the emperor of 
Russia, of the size of a pigeon’s egg ; and ano- 
ther in the possession of the Great Mogul, which 
is said to weigh 280, and which, in a rough state, 
weighed 793 carats—From the fact that trans- 
parent inflammable bodies refract light in a ra- 
tio greater than their densities, Sir Isaac Newton 
conjectured that the diamond might consist of 
an unctuous matter coagulated. The Florentine 
academicians had rendered its combustibility 
probable, by exposing it to the solar rays of a 
powerful burning-glass, and observing that it 
gradually disappeared, or was consumed. Sub- 
sequent experiments settled the question, by 
proving, that the diamond lost none of its weight 
when calcined out. of contact with the air; but, 
on the contrary, that it was dissipated when 
heated in contact with this fluid. It still re- 
mained, however, to be discovered, what was the 
true nature, of the diamond. This was accom- 
plished by Lavoisier, who enclosed diamonds in 
jars filled with atmospheric air or oxygen gas, 
and, after having caused them to disappear by 
the heat of a burning-glass, examined the air in 
| in nature. The faces of its crystals are very fre- 
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