BRASS. 
passes into the brandy. 
probable that the aromatic portion condenses 
sooner than a strong alcoholic liquid, for the 
finest kinds are only distilled to the spec. grav. 
0922 at the farthest, and by redistillation to 
procure a stronger liquor, much of the aroma is 
lost, or rather remains in the residue. The effect 
_ of heat on several of the substances noted above 
as constituents of wines, merits the attention of 
the distiller, for a little too high temperature, 
especially where the still is exposed to the direct 
action of the fire, is apt to generate empyreuma- 
tic and other products, which are unlikely to add 
to the quality of the liquor. To manufacture a 
brandy artificially, add to about 10 gallons of 
a pure alcoholic liquid, diluted much below the 
strength required, a pound of crude argol dis- 
solved in water and a portion of good brandy, and 
distil the mixture with a gentle heat. Add to the 
distillate a little acetic ether and colour it with 
burned sugar. Astringency may be imparted by 
a few drops of tincture of catechu or pure tannic 
acid. The addition of brandy and crude argol 
introduces a portion of oinanthic ether, which, 
with the acetic ether, imparts the peculiar taste 
of genuine Cognac. 
BRANK. See Buckwurat. 
BRASILETTO. See Cmsanprnta. 
BRASS. Analloy essentially composed of cop- 
per and zinc, often containing small quantities of 
iron, lead, and tin, either as accidental or de- 
signed ingredients. It was formerly made by 
igniting metallic copper with calcined calamine 
and charcoal. At present it is chiefly made by 
the direct fusion of the two metals, in conse- 
quence of the improved processes for obtain- 
| Ing zinc. The composition of good brass is 
| about 2 parts copper to 1 part zinc, but the rela- 
tive proportions of these two metals are varied, 
and small quantities of others are introduced, 
according to the destination of the brass. <A 
little iron hardens it and diminishes its tenacity 
and malleability. We usually find traces of tin 
and lead in it, arising partly from solder in the 
old brass used in the manufacture, and the lead 
arising from a small quantity having been in 
the copper. Tin renders it harder and stiffer, 
and even a 4 per cent. alters its ductility. The 
_presence of lead renders it better adapted to the 
lathe, in consequence of the harshness it imparts 
toit. Pure brass without these metals is very 
ductile, may be easily drawn into thin wire, 
rolled, or extended by the hammer. A small 
quantity of zinc gives a reddish brass. The above 
formula gives a golden colour ; a larger quantity 
of zinc produces a greenish yellow; and when the 
alloy contains more than half zinc, it is bluish 
grey. The density of the alloy is greater than 
the mean of that of its constituents. 
Observed 
cee | fe) Meee) hanes 
70 30 8-443 8-390 
80 20 8-940 8-560 
Tempering diminishes its density, thus the 
In Cognac, &c., it is 
BRASSICA. ot} 
above of spec. grav. 8:94 after tempering was 8°92, 
another of density 8°344 became 8°250, The same 
operation also diminishes the tenacity and hard- | 
ness of brass. The density increases in propor- 
tion to the copper, and may even equal that of 
copper itself, hence it varies between 82 and 
8°95. 
BRASSICA. <A highly important genus of 
herbaceous plants, forming the type of a subdi- 
vision of the cruciferous family.. The genera 
additional to itself comprised in this subdivision 
are sinapis, moricandia, diplotaxis, and eruca. 
The brassica genus has entire stamens, undi- 
vided petals, an equal and slightly spreading 
calyx, a long, slender, and many-seeded pod, 
spherical seeds, and a radicle contained in the 
cavity of the folded cotyledons. Its chief spe- 
cies is the oleracea; and this, inclusive of its nu- 
merous varieties, is the subject of our articles 
CABBAGE, BorEcoLE, Kout-Rasi, Broccont, and 
CAULIFLOWER. Its species of next importance 
are campestris, rapa, and napus; and these are 
the subjects of our articles Turnip and Rapxr. 
Twenty-five species additional to these are grown 
in Great Britain ; one of these, B. monensis, grows 
wild on the shores of the Isle of Man, and the 
others have been introduced from China, St. 
Helena, Minorca, and the continent of Europe; 
and nine or ten other species have been described 
by botanists. Two of the introduced species 
have silicles raised above the receptacle on short 
pedicels; and all the others, like the cabbages 
and the turnips, have sessile silicles. Six are 
perennials ; nine are annuals ; and all the rest are 
biennials. Only one, besides the turnips, B. pre- 
cox, is bulbous-rooted; and only this and the 
Chinese, 5. chinensis, are cultivated for econo- 
mical or practical purposes. 
A serious mistake is still general, and till of 
late was universal, in Great Britain, as to the 
kinds of brassica which are most productive of 
the oils usually called rape and sweet oil. The 
Brassica napus oleiferus is the kind which Bri- 
tish farmers have been accustomed to grow for 
oil; but the Brassica campestris olevfera is the kind 
which yields by far the largest produce. In Bel- 
gium, the latter kind is usually sown, about the 
middle of June, on a piece of well-manured gar- 
den ground; it is transplanted after harvest, into 
good-conditioned fields, which have been once 
ploughed after the removal of the corn; in No- 
vember, it is cleaned. and either top-dressed or 
watered with liquid manure; and it then stands 
over the winter, blossoms in spring, and soon 
afterwards runs to seed. “It would be desirable 
for agriculture,” says De Candolle, “that, in all 
countries, cultivators would examine whether 
the plant they rear for oil is the Brassica cam- 
pestris oleifera, or the Brassica napus oleiferus ; 
which can easily be ascertained by observing 
whether the young plant is rough or smooth; if 
hispid, it is the Brassica campestris,—if glabrous, 
the Brassica napus. Experiments made by Gau- 
\ 
rr re 
