NEG 
quantities, negative signs, negative powers, 
&c. See Algebra. 
Our words and idea, says Dr. Watts, are 
so unhappily linked together, that we can 
never know which are positive, which nega- 
tive ideas, by the words that express them : 
for some positive terms denote a negative 
idea, as dead ; and there are both positive 
and negative terms invented to signify the 
same and contrary ideas, as unhappy and 
miserable. To this may also be added, that 
some words, which are negative in tlie ori- 
ginal language, seem positive in English, as 
abyss. The way, therefore, to know whe- 
ther any idea be negative or not, is to con- 
sider whether it primarily implies the ab- 
sence of any positive being, or mode of be- 
ing ; if so, then it is a negative idea, other- 
wise a positive one. 
Negative sign, the sign of subtraction, 
or that whicli denotes something in defect. 
Tire nse of the negative sign in algebra is 
attended with several consequences that at 
first sight are admitted with some difficulty, 
and has sometimes given occasion to notions 
that seem to have no real foundation. This 
sign implies, that the real value of the quan- 
tity represented by the letter to which it is 
prefixed, is to be' subtracted ; and it serves, 
with the positive sign, to keep in view what 
elements or parts enter into the composition 
of quantities, and in what manner, whether 
as increments or tlecrements, that is, whe- 
ther by addition or subtraction, which is of 
the greatest use in this art. Hence it 
serves to express a quantity of an opposite 
quality to a positive, such as a line in a con- 
trary position, a motion with opposite di- 
rection, or a centrifugal force in opposition 
to gravity ; and thus it often saves the trou- 
ble of distinguishing, and demonstrating se- 
parately, the various cases of proportions, 
and preserves their analogy in view. But 
as the proportions of lines depend on their 
magnitude only, without regard to their 
position ; and motions and forces are said 
to be equal or unequal, in any given ratio, 
without regard to their directions ; and in 
general the proportion of quantities relates 
to their magnitude only, whhout determin- 
ing whether they are to be considered as 
increments or decrements ; so there is no 
ground to imagine any other proportion of 
+ u and — b, than that of the real magni- 
tudes of the quantities represented by a 
and b, whether these quantities are, in 
any particular case, to be added or sub- 
tracted. 
NEGRO, a name given to a variety of 
NEP 
the human species, who are entirely black, 
and are found in the torrid zone, especially 
in that part of Africa which lies between tlie 
tropics. See Man; Slave; Slave trade. 
NEPA, in natural history, mafei'-scorpion, 
a genus of insects of the order Hemiptera, 
Snout inflected ; antennae short ; wings four, 
folding cross-wise, coriaceous on the upper 
part ; fore legs cheliform ; the other four 
formed for walking. There are fourteen 
species in three divisions, viz. A. Antennae 
palmate, without a lip. B. Antenn^B pal- 
mate ; lip short, widely emarginate. C. Lip 
projecting, rounded. N. linearis, described 
by Mr. Donovan, has a tail ending in two 
bristles, as long as the body ; thorax of one 
colour; foreshanks with a spine in the 
middle. I'he body is brown, cylindrical ; 
abdomen red ; the eggs are oblong, and 
armed at one end with two bristles, and 
are found inclosed in the culm or stem of 
l ushes, with hairs standing out. 
NEPENTHES, in botany, a genus of 
the Dioecia Syngenesia class and order. 
Essential character; calyx four- parted; co- 
rolla none :.male, filament one, with many 
anthers, connected into a peltate head : fe- 
male, style none; stigma large, peltate 
four-lobed; capsule four-celled, with many 
arilled seeds. There is but one species, 
viz. N. distillatoria, a native of the island of 
Ceylon. 
The nepenthes may justly be classed 
among the most singular productions of the 
vegetable world. The plant has always exr 
cited the admiration of tliose who have ex- 
amined its structure, with a view to the 
contrivance which is so strikingly exhibited 
in the formation of its leaves. The nepen- 
thes is a native of India : it is an herba- 
ceous plant, with thick roots and a simple 
stem, crowned with flowers disposed in 
bunches. The leaves are alternate, partly 
embracing the stem at their base, and ter- 
minated by tendrils, each of which supports 
a deep, membranous urn, of an oblong 
shape, and closed by a little valve like the 
lid of a box. This appendage to the leaf 
appears to be as designed and studied a 
piece of mechanism as any thing we can 
meet with in nature's more complicated 
productions. The leaf, as we have already 
said, is terminated by a deep oblong urn ; 
thks, in general, is filled with a sweet lim- 
pid water. In the morning, the lid is closed, 
but it opens during the heat of the day, and 
a portion of the water evaporates ; this is 
replenished in the night, and each morning 
the vessel is full, and the lid shut. The 
