A R A 
ARB 
133 
animal. The young no sooner quit their 
j egg than they begin to spin. Indeed their 
threads can scarcely be perceived, but the 
webs may; and no wonder, there being often 
400 or .500 little spiders concurring to the 
same work. There are some kinds of spi- 
j tiers so small at their birth, that they are not 
visible without a microscope. There are 
usually found an infinity of these in a cluster, 
and they only appear like a number of red 
; points : and yet there are webs found under 
them, though almost imperceptible. What 
must be the tenuity of one of these threads ? 
I Mr. Lewenhock has computed that 100 of 
j the single threads of a full grown spider are 
j not equal to the diameter of the hair of his 
beard ; and consequently, if the threads and 
hair are both round, ten thousand such 
threads are not bigger than such a hair. 
Garden-spiders, (Plate, Nat. Hist. iig. 30.) 
particularly the short-legged species, y ; eld silk 
which has been judged scarcely inferior to 
thatof the silkworm. Mr. Bon of Langue- 
doc, about 70 years ago, contrived to'manu- 
] facture from it a pair of silk stockings and 
! mittens, of a beautiful natural grey colour, 
| which were almost as handsome and strong 
j as those made with common silk ; and he 
| published a dissertation concerning the dis- 
| co very. But M. Reaumur, being appointed 
by the Royal Academy to make a farther 
j enquiry into this new silk work, raised several 
objections and difficulties against it; The 
] sum of which amounts to this. The natural 
j fierceness of the spider renders them unlit to 
I be bred and kept together. Four or five 
thousand being distributed into cells, 50 in 
some, 100 or 200 in others, the big ones soon 
killed and eat the less, so that in a short time 
there were scarcely left one or two in each 
cell ; and to this inclination of mutually 
I eating one another M. Reaumur ascribes the 
scarcity of spiders, considering the vast num- 
bers of eggs they lay. But lie affirms, that 
the silk of the spider is nut one-fifth of the 
strength of that of the silk-worm. Add to 
this, that the Spider's thread cannot be wound 
off as that of the silk-worm may, but must of 
1 necessity be carded ; by which means being 
torn in pieces, its evenness which contributes 
| much to the lustre, is destroyed. Again, .spi- 
• ders furnish much less silk than the worms: 
the work of 12 spiders only equals that of 
j one silk-worm ; and a pound of silk will re- 
i quire at least 27,648 spiders. 
The species of aranea enumerated bv natu- 
ralists amount to upwards of 50; of which 
it may here suffice to mention a few of the 
most remarkable. 
1. Aranea aquatica, or the water-spider, 
frequents the fresh waters of Europe. But 
it is in some sort amphibious : for it can live 
on land as well as in the water, and comes 
often on sliore for its food ; yet it swims well 
in water, both on its belly and back : it is 
distinguishable by its brightness. In the 
water its belly appears covered with a silver 
varnish, which is only a bubble of air attached 
to the abdomen by means of oily humours 
which transpire from its body, and prevent 
the immediate contact of the water. This 
bubble of air is made the substance of its 
dwelling, which it constructs under water : 
for it fixes several threads of silk, or such fine 
matter, to the stalks of plants in the water ; 
and then ascending to the surface, thrusts the 
hinder part of its body above water, drawing 
A R A 
it back again with such rapidity, that it at- 
taches underneath a bubble of air, which it 
has the art of de fining under water, by 
placing it underneath the threads, and which 
it binds like a covering almost all around the 
air bubble. Then it ascends again for an- 
other air bubble ; and thus proceeds iflitil 
it lias constructed a large aerial apartment 
under water, which it enters into or quits at 
pleasure. It lodges during the winter in 
empty shells, which it dextrbusly shuts up 
with a web. 
2 . Aranea Avicularia, is a native of Ame- 
rica, and feeds upon small birds, insects, &c. 
The bite of this spider is accounted as veno- 
inous as that of the serpent. 
3. Aranea calycina, lives in the cups of 
flowers, after the flower-leaves have fallen 
off; and catches bees, and other flies, when 
they are in search of honey. 
4. Aranea Cucurbitina has a globular yel- 
low belly, with a few black spots. It lives 
in the leaves of trees, and incloses its eggs 
in a soft net. 
5. Aranea Diadema is the largest spider 
which this country produces. The abdomen 
is of an oval form, downy, and of a ruddy 
yellow colour. The upper part is beauti- 
fully adorned with black and white circles 
and clots, having* a longitudinal band in the 
middle, composed of oblong and oval shaped 
pearl coloured spots, so arranged as to re- 
semble a fillet, similar to those worn by the 
eastern kings. The legs are of a fine pale 
green colour ; annulated with dark purple 
or black. It inhabits the birch tree. 
6. Aranea Fasciata, with yellow bands 
round the belly, and dusky rings on the legs, 
is a native of Barbary, and is as large as the 
thumb. It inhabits hedges and thickets : its 
webs have large meshes, and it resides in 
the centre. Twelve of these spiders, by 
way of experiment, were shut up together ; 
and, after a battle of eight days, the strong- 
est only remained alive. 
7. Aranea Eiinbriata, has a black oblong 
belly, with a white line on each side, and 
dusky coloured legs. It lives in water, upon 
the surface of which it runs with great swift- 
ness. 
8. Aranea Ilolosericea, has an oval belly 
covered with a down, like velvet; at the 
base, or under part, it has two yellow spots. 
It is found in the folded leaves of plants. 
0. Aranea Labyrinthica, with a dusky 
oval belly, a whitish indented line, and "a 
forked anus. The web of this species is 
horizontal, with a cylindrical well or tube in 
the middle. 
10. Aranea Ocellata, has three pair of 
eyes on its thighs. It is about the same size 
with the tarantula, of a pale colour, with a 
black ring round the belly, and two large 
black spots on the sides of the breast. It is 
a native of China. 
11. Aranea Saccata, lives in the ground, 
and carries a sack with its eggs, wherever 
it goes. This sack it glues to its belly, and 
will rather die than leave it behind. 
12. (1) Aranea Tarantula has the breast 
and belly of an ash-colour; the legs are 
likewise ash coloured, with blackish rings on 
the under part ; two of its eyes are larger 
than the other, red, and placed in the front ; 
four other eyes are placed in a transverse 
direction towards the mouth. It is a native 
of Italy, Cyprus, Barbary, and the East 
Indies. It lives in bare fields, where the 
lands are fallow, but not very hard. Its 
dwelling is about four inches deep, and Half 
an inch wide; at the bottom it is curved, 
and there the insect sits in wet weather, and 
cuts its way out if water gains upon it. It 
weaves a nest at the mouth of the hole. 
These spiders do not live quite a year. In 
July they shed their skin. They lay about 
730 eggs, which are hatched in the spring ; 
but the parent does not live to see her pro- 
geny, as she expires early in the winter. 
The ichneumon fiv is their greatest enemy. 
The bite of the tarantula is said to occasion 
an inflammation in the part, which in a few 
hours brings on sickness, difficulty of breath- 
ing, and universal faintness; the same symp- 
toms return annually, in some cases, for 
several years; and at last terminate in death. 
Music, it has been pretended, is the only 
cure. Such are the circumstances that have 
been generally related, and long credited, 
concerning the bite of this animal. But it 
is now generally agreed, that no such effects 
attend th ; s bite ; and that the exhibitions of 
dancing to music by persons pretending to 
be so affected, are only villainous deceptions 
to excite the compassion and extract the mo- 
ney of the spectators. Plate Nat. Hist. fig. 31. 
13. Aranea Viatica, or wanderer, is gene- 
rally of a yellow colour, more or less deep. 
It is found upon plants; and is a lively, 
active, indefatigable hunter. Without any 
motion of the head, which is furnished with 
immoveable eyes, it perceives all the flies 
that hover round about, does not scare 
them, but stretches over them its arms, fur- 
nished with feathers, which prove nets in 
which their wings entangle. It is said to sit 
on its eggs; which, however, it often carries 
about with it, wrapt up in a hall of white silk.' 
Aranea, in mineralogy, a silver ore 
found only in the mines of Potosi. It owes 
its name to the faint resemblance it bears to 
a cobweb, being composed of threads of 
pure, silver, which to the sight appear like 
silver lace, when burnt to separate the silk 
from it. 
ARBITER, in civil law, a judge nomi- 
nated by the magistrate, or chosen volun- 
tarily by two parties, in order to decide 
their differences according to law. 
The civilians' make this difference between 
arbiter and arbitrator : thongh both ground, 
their power on the compromise of the par- 
ties, yet their liberty is different; for an 
arbiter is to judge according to the usages 
of the law, but the arbitrator is permitted 
to use his own discretion, and accommodate 
the difference in the manner that appears to 
him most just and equitable. 
ARBITRATION, a power given by two 
or more contending parties, to some person 
or persons to determine the dispute between 
them. Matters relating to a freehold, debts 
due on bond, and criminal offences, are not 
to be arbitrated. If the party injured by a 
criminal act, however, proceeds by way of 
civil action, as in assadit or libel, ixc. the 
damages may be submitted to arbitration ; 
also in case of a breach of promise of mar- 
riage. The submission to arbitration given 
by the parties must be an agreement or bond 
upon a stamp, and must not be construed 
strictly but largely according to the intent 
of the parties submitted. It commonly con- 
tains a clause to protect the arbitrators from 
