WEI 
Cross, or net-weaving, is a separate branch 
of the art, and requires a loom particularly 
constructed for the purpose. 
Spots, Brocades, and Lappets, are pro- 
duced by a combination of the arts of plain, 
tweeled, and gauze weaving ; and, as in 
every other branch of the art, are produced 
in all their varieties by different ways of 
forming the sheds, by the application of 
heddles, and their connections with the 
treddles which move them. Indeed, the 
whole knowledge of the art consists in this 
part of the apparatus of a loom. 
In drawing up the foregoing account of 
the art of weaving we have laboured under 
inconveniences of no small magnitude. The 
many different kinds of cloth ; the almost 
infinite variety of ways, though all on the 
same general principle, of constructing 
them ; the different formation of apparatus in 
making different cloths; and, lastly, the 
want of uniformity in the technical phraseo- 
logy of the art, have all tended to render 
cur descriptions far more intricate and dif- 
ficult than they otherwise would have been. 
The assistance, however, which we have de- 
rived from the very excellent “ Essays on 
the Art of Weaving,” by Mr. Duncan, 
ought not to pass by us unacknowledged. 
It is a most curious and valuable publica- 
tion, embracing almost every thing neces- 
sary to be known concerning the art on 
which it professes to treat. 
WEBERA, in botany, a genus of the 
Pentandria Monogynia class and order. 
Essential character : contorted ; berry in- 
ferior, two-celled, ceils one seeded ; style 
elevated ; stigma club-shaped ; calyx five- 
cleft. There are three species. 
WEDGE, one of the mechanical powers, 
as they are called. The wedge is a trian- 
gular prism, whose bases are equilateral 
acute-angled triangles. See Mechanics. 
WEEK, in chronology, a division of time 
comprising seven days. See Chrono- 
logy. 
WEIGELIA, in botany, so named in ho- 
nour of Christ. Ehrenfr. Weigel ; a genus of 
the Pentandria Monogynia class and order. 
Essential character : calyx five-leaved ; co- 
rolla funnel-form ; style from the base of 
the germ ; stigma peltate ; seed one. There 
are two species, viz. W. japonica, and 
W. corceensis, both natives of Japan. 
WEIGHT, in physics, is a quality in na- 
tural bodies, by which they tend towards 
the centre of the earth. See Gravitation. 
Weight may be distinguished into absolute, 
specific, and relative. It is demonstrated 
WEI 
by Sir Isaac Newton : 1. That the weights 
of all bodies, at equal distances from the 
centre of the earth, are proportional to the 
quantities of matter that each contains.' 2. 
On different parts at the earth’s surface, 
the weight of the same body is different ; 
owing to the spheroidal figure of the earth, 
which causes the bodies on the surface to 
be nearer the centre in going from the 
equator towards the poles ; and the increase 
of weight is nearly in proportion to the 
square of the sine of the latitude : the 
weight at the equator to that at the pole 
being as 229 : 230 ; or the whole increase of 
weight from the equator to the pole is the 
229th part of the former. 3. That the 
weights of the same body, at different dis- 
tances above the earth, are inversely as the 
squares of the distances from the centre. 
So that a body at the distance of the moon, 
which is 60 semi-diameters from the earth’s 
centre, would weigh only P®*'*- 
what it weighs at the surface of the earth. 
4. That at different distances within the 
earth, or below the suiface, the weights of 
the same body are directly as the distances 
from the earth’s centre ; so that at half 
way toward the centre a body would weigh 
but half as much, and at the centre it would 
weigh nothing at all. 5. A body immersed 
in a fluid, which is specifically lighter than 
itself, loses so much of its weight as is equal 
to the weight of a quantity of the fluid of the 
same bulk with itself. Hence a body loses 
more of its weight in a heavier fluid than in a 
lighter one, and therefore it weighs more in 
a lighter fluid than in a heavier one. 
Tiie weight of a cubic foot of water is 
1000 ounces, or 62|i6. avoirdupois ; this, 
multiplied by 32, gives 200016. the weight 
of a ton : hence eight cubic feet formerly 
made a hogshead, and four hogsheads a ton, 
in capacity as well as in weight. Measures 
for corn, coals, and other dry articles, were 
constructed on the same principle. A bushel 
of wheat, assumed as a general standard for 
all sorts of grain, weighed 62116. eight of 
these make a quarter, and four quarters, or 
32 bushels, a ton weight. Coals were sold 
by the chaldron,, and supposed to weigh a 
ton, though in reality it weighs much more. 
Hence a ton weight is the common stan- 
dard for liquids, wheat, and coals. Had 
this analogy been adhered to, the confusion 
which is occasioned by different local weights 
would have been avoided. 
To regulate the weights and measures of 
a country is a branch of the sovereign’s pre- 
rogative. For the public conveniencej 
