BUT 
account of their texture when newly pre- 
pared. According to this system, there 
are the butters of antimony, arsenic, bis- 
muth, and tin. They all agree in the fol- 
lowing particulars ; they are formed by sub- 
limation ; their texture is not unlike that of 
butter in warm weather ; tliey are decom- 
posable by being dropped into pure water, a 
precipitation of white oxide taking place. 
There are likewise vegetable butters, a term 
applied to those vegetable expressed oils 
that require a greater heat tlian that of the 
atmosphere to keep them in a fluid state : 
of these the palm oil is best known : a simi- 
lar oil may be obtained from the cocoa nut ; 
and the celebrated Park found in Africa a 
tree, called by the natives shea, from the 
fruit of which a tolerably pure butter was 
obtained. 
Butter milk, a kind of serum that re- 
mains behind, after the butter is made. 
BUTTERFLY, the English name of a 
numerous genus of insects, called by zoolo- 
gists papilio. See Papilio. 
BU'ErERY, a room in the houses of no- 
blemen and gentlemen, belonging to the 
butler, where he deposits the utensils be- 
longing to his office, as table-linen, napkins, 
pots, tankards, glasses, cruets, salvers, 
spoons, knives, forks, pepper, mustard, &c. 
BUTTNERIA, in botany, so named from 
David Sigismunda Augustus Buttner ; a ge- 
nus of the Pentandria Monogynia class and 
order. Natural order of Columnifer®. Mal- 
vace®, Jussieu. Essential character; co- 
rolla five-petalled ; filaments at the top con- 
nate with the petals ; capsule five-grained, 
nuiricate. There are fliree species; cir. 
B. scabra, is a perennial plant, from three 
to five feet high, with alternate, long, angu- 
lar branches, armed with cartilaginous 
prickles ; at the axils of the leaves, stem, 
and branches, the flowers are produced 
singly on short peduncles : it is found at 
Cayenne. B. carthaginensis is a shrub 
branching and spreading on every side, in 
manner of the common bramble ; racemes 
short, aggregate, and axillary on the young 
branches ; flowers w'ithout smell, white, 
and very numerous : native of Carthagena 
and St. Domingo; flowering in September 
and October; and B. microphylla differs 
but little from the foregoing, in having the 
trunk and branches larger and round, the 
peduncles one-flowered, and the corolla pur- 
ple and white, variegated : it was found in 
the island of St. Domingo by Jacquin, and 
brought into Europe. 
BUTTOCK of a ship, is that part of her 
BUT 
which is her breadth right a-stern, from the 
tack upwards; and a ship is said to have a 
broad or a narrow buttock, according as 
she is built, broad or narrow at the tran. 
sum. 
BUTTOMUS, in botany, a genus of the 
Enneandria Hexagynia. Natural order of 
Tripetaloide®. Junci, Jussieu. One of the 
connecting links between lilies and rushes. 
Essential character ; calyx none ; petals 
six; capsule six, many-seeded. There is 
but one species ; viz. B. umbellatus, flower- 
ing rush or gladiole, has a perennial root ; 
leaves ensiform, long, triangular, smooth, 
quite entire, spongy, at bottom sheathing, 
at top flat and twisted ; flowers to thirty, 
each on a single, round, smooth peduncle, 
from an inch to about a finger’s length, 
forming an upright umbel, surrounded at 
bottom by an involucre of three withering 
membranous sheaths, besides a smaller sti- 
pule to each peduncle ; corolla very hand- 
some and large, of a bright flesh colour ; fi- 
laments placed on a regular circle on the 
receptacle ; the pollen is of a bright yellow 
colour; germ nearly triangular. This is the 
only plant of the class Eni'.eandria which 
grows wild in Britain. 
BUTTON, an article of dress, serving to 
fasten cloaths tight about the body, made 
of metal, silk, mohair, &c. in various forms. 
Metal buttons are either cast in moulds, in 
the manner of other small works, or made 
of thin plates of gold, silver, or brass, whose 
structure is very ingenious. 
Of the mamfiicture of metal huttoiis. 
These are originally formed in two diffe- 
rent w'ays ; the blanks are either pierced 
out of a large sheet of metal with a punch 
driven by a fly-press, or cast in a pair of 
flasks of moderate size, containing 10 or 12 
dozen each. In this latter case, the shanks 
are previously fixed in the sand, exactly in 
the centre of the impression formed by each 
pattern, so as to have their extremities im- 
mersed in the melted metal when poured 
into the flask, by wliich means they are con - 
sequently firmly fixed in the button when 
cooled. The former process is generally 
used for yellow buttons, and the latter for 
those of white metal. We shall first give 
an instance of the former mode of proce- 
dure as used in the manufacture of gilt but- 
tons. The gilding metal is an alloy of cop- 
per and zinc, containing a smaller propor- 
tion of the latter than orduiary brass, and is 
made either by fusing together the copper 
and zinc, or by fusing brass with the requi- 
site additional proportion of copper. Thi§ 
