LAM 
screw in the same direction as the wire of 
the handle, t, to supply air to this part. 
AVhen the urn is to be filled w'ith oil, it is 
unscrewed at t, and the oil poured in at 
the hole in tube v : the bole must tlien be 
closed, by pushing down the handle, t: the 
oil cannot now get out, and the urn is 
screwed into its place ; when the handle, t, 
is pushed down the hole is opened, by re- 
moving the tube, m, from before the hole in 
the pipe, v: the oil now runs out, the air 
entering at tlie same hole, until it rises in 
the cistern at the end of the pipe, B, above 
the level of the hole ; the air cannot now 
enter, and consequently the oil will not 
come out, until by the burning of the lamp 
the oil is drawm down below the hole, a 
bubble of air then gets into the urn, and an 
equivalent drop of oil runs down : by this 
means, though the lamp is always plentifully 
supplied, yet it never runs over. 
LAMP black. See Colour. 
LAMPYRIS, in natural history, fire fiy, 
a genus'of insects of the order Coleoptera. 
Antennas filiform ; four feelers ; shells flex- 
ile; thorax flat, semi-orbicular, surround- 
ing and concealing the head ; segments of 
the abdomen terminating in folded papillas ; 
female usually apterous. There are nearly 
sixty species, in four divisions, viz. A. feel- 
ers subclavate : B. fore -feelers hatchet- 
shaped : C. feelers sub-filiform : D. first 
joint of the feelers thicker and truncate. 
The first of these divisions is subdivided in- 
to those which have entire horny lips ; and 
into those with an emarginate membrana- 
ceous lip. The body of the insect in this 
genus is oblong, with the sides formed into 
a kind of soft papilte, lapping over each 
other. L. noctiluca, or common glow- 
worm, is seen during the summer months, 
on diy banks, about woods, pastures, and 
hedgeways, exhibiting, as soon as it is dusk, 
vivid and phosphoric splendour, in form of 
a round spot of considerable size. The 
animal itself, which is the female insect, 
measures about three quarters of an inch 
in length, and is of a dull, earthy-brown co- 
lour on the upper parts, and beneath more 
or less tinged with rose colour, with the 
two or three last joints of the body of a 
pale or whitish sulphur colour. It is from 
these parts that the phosphoric light pro- 
ceeds. The body, exclusive of the thorax, 
consists of ten joints. The larva and pupa 
do not greatly differ from the complete in- 
sect, but the phosphoric light is strongest 
in the complete animal. The male is 
smaller than the female, and is provided 
LAN 
with wings and wing-sheaths ; it is very un- 
common; and it is not determined whether 
it be luminous or not. Naturalists uave 
commonly supposed, that the splendour of 
the female is designed for the purpose of 
attracting the male. In Italy, the flying 
glow-worm is extremely common ; and it is 
said that, on grand occasions, ladies use 
them as ornaments for their head-dress in 
evening parties. 
LANA, in botany, wool, a species of pu- 
bescence, down, or velvet, which serves to 
screen the leaves, covered with it, from the 
heat : this appearance is very conspicuous 
in the horehound, woolly thistle, &c. 
Lana philosophica,. flowers of zinc. See 
Zinc. 
LANARIA, in botany, a genus of the 
Hexandria Monogynia class and order. Na- 
tural order of Ensatae. Irides, Jussieu. Es- 
sential character : corolla superior, woolly, 
longer than the filaments ; border six-part- 
ed, somewhat .spreading; capsule three- 
celled. There is but one species, viz. L. 
plumosa, woolly lanaria, a native of the 
Cape of Good Hope. 
LANCET, a chi'rurgical instrument, 
sharp-pointed, and two-edged, chiefly used 
for opening veins in the operation of phle- 
botomy,! or bleeding ; also for laying open 
abscesses, tumours, &c. 
LANGUAGE. 1. Man, it has frequently 
been said, is the only animal possessed of 
speech, and if we use this term as implying 
the expression of a train of ideas by articu- 
late sounds, it may perhaps be esteemed the 
best criterion of distinction between man 
and the inferior animals. It is not easy to 
fix upon one which shall be universally ap- 
plicable ; but the same difficulty frequently 
occurs in the attempt to ascertain the ex- 
act boundary betw'een the characteristics of 
one class of being and those of another: 
for instance, the naturalist finds it a puzzling 
problem to ascertain the characteristic dif- 
ference between the animal and the vege- 
table kingdom. Some of the most intelli- 
■gent of the brute creation often astonish us 
by actions which can proceed only from 
powers of intellect similar to those which 
we possess. All the mental powers, except 
sensation, are probably the modifications of 
tlie principle of association : it is acknow- 
ledged that brutes possess this in a consider- 
able degree, and it is probable that to the 
difference in the extent of this principle of 
its activity and direction, we are to attribute 
the mental difference between one animal and 
another. There is, perliaps, less difference 
