Animals in general are sagacious in proportion as they cultivate
society. The elephant and the beaver show the greatest signs of this
when united; but when man intrudes into their communities they lose
all their spirit of industry and testify but a very small share of
that sagacity for which, when in a social state, they are so
remarkable.
Among insects, the labors of the bee and the ant have employed the
attention and admiration of the naturalist; but their whole sagacity
is lost upon separation, and a single bee or ant seems destitute of
every degree of industry, is the most stupid insect imaginable,
languishes for a time in solitude, and soon dies.
Of all the solitary insects I have ever remarked, the spider is the
most sagacious; and its actions, to me who have attentively considered
them, seem almost to exceed belief. This insect is formed by nature
for a state of war, not only upon other insects, but upon each other.
For this state nature seems perfectly well to have formed it. Its head
and breast are covered with a strong natural coat of mail, which is
impenetrable to the attempts of every other insect, and its belly is
enveloped in a soft, pliant skin, which eludes the sting even of a
wasp. Its legs are terminated by strong claws, not unlike those of a
lobster; and their vast length, like spears, serve to keep every
assailant at a distance.
Not worse furnished for observation than for an attack or a defense,
it has several eyes, large, transparent, and covered with a horny
substance, which, however, does not impede its vision. Besides this,
it is furnished with a forceps above the mouth, which serves to kill
or secure the prey already caught in its claws or its net.
Such are the implements of war with which the body is immediately
furnished; but its net to entangle the enemy seems what it chiefly
trusts to, and what it takes most pains to render as complete as
possible. Nature has furnished the body of this little creature with a
glutinous liquid, which, proceeding from the anus, it spins into
thread, coarser or finer, as it chooses to contract or dilate its
sphincter. In order to fix its thread when it begins to weave, it
emits a small drop of its liquid against the wall, which hardening by
degrees, serves to hold the thread very firmly. Then receding from its
first point, as it recedes the thread lengthens; and when the spider
has come to the place where the other end of the thread should be
fixt, gathering up with its claws the thread which would otherwise be
too slack, it is stretched tightly and fixt in the same manner to the
wall as before.
In this manner it spins and fixes several threads parallel to each
other, which, so to speak serve as the warp to the intended web. To
form the woof, it spins in the same manner its thread, transversely
fixing one end to the first thread that was spun, and which is always
the strongest of the whole web, and the other to the wall. All these
threads being newly spun, are glutinous and therefore stick to each
other wherever they happen to touch; and in those parts of the web
most exposed to be torn, our natural artist strengthens them, by
doubling the threads sometimes sixfold.
Thus far naturalists have gone in the description of this animal; what
follows is the result of my own observation upon that species of the
insect called a house spider. I perceived about four years ago a large
spider in one corner of my room, making its web; and tho the maid
frequently leveled her fatal broom against the labors of the little
animal, I had the good fortune then to prevent its destruction; and I
may say it more than paid me by the entertainment it afforded.
In three days the web was with incredible diligence completed; nor
could I avoid thinking that the insect seemed to exult in its new
abode. It frequently traversed it round, examined the strength of
every part of it, retired into its hole, and came out very frequently.
The first enemy, however, it had to encounter, was another and a much
larger spider, which, having no web of its own, and having probably
exhausted all its stock in former labors of this kind, came to invade
the property of its neighbor. Soon, then, a terrible encounter ensued,
in which the invader seemed to have the victory, and the laborious
spider was obliged to take refuge in its hole. Upon this I perceived
the victor using every art to draw the enemy from his stronghold. He
seemed to go off, but quickly returned; and when he found all arts
vain, began to demolish the new web without mercy. This brought on
another battle, and, contrary to my expectations, the laborious spider
became conqueror, and fairly killed his antagonist.
Now, then, in peaceable possession of what was justly its own, it
waited three days with the utmost impatience, repairing the breaches
of its web, and taking no sustenance that I could perceive. At last,
however, a large blue fly fell into the snare, and struggled hard to
get loose. The spider gave it leave to entangle itself as much as
possible, but it seemed to be too strong for the cobweb. I must own I
was greatly surprized when I saw the spider immediately sally out,
and in less than a minute weave a new net around its captive, by which
the motion of its wings was stopt; and when it was fairly hampered in
this manner, it was seized and dragged into the hole.
In this manner it lived in a precarious state; and nature seemed to
have fitted it for such a life, for upon a single fly it subsisted for
more than a week. I once put a wasp into the net; but when the spider
came out in order to seize it as usual, upon perceiving what kind of
an enemy it had to deal with, it instantly broke all the bands that
held it fast and contributed all that lay in its power to disengage so
formidable an antagonist. When the wasp was at liberty, I expected the
spider would have set about repairing the breaches that were made in
its net, but those it seems were irreparable; wherefore the cobweb was
now entirely forsaken, and a new one begun, which was completed in the
usual time.
I had now a mind to try how many cobwebs a single spider could
furnish; wherefore I destroyed this, and the insect set about another.
When I destroyed the other also its whole stock seemed entirely
exhausted, and it could spin no more. The arts it made use of to
support itself, now deprived of its great means of subsistence, were
indeed surprizing. I have seen it roll up its legs like a ball and lie
motionless for hours together, but cautiously watching all the time.
When a fly happened to approach sufficiently near, it would dart out
all at once, and often seize its prey.
Of this life, however, it soon began to grow weary, and resolved to
invade the possession of some other spider, since it could not make a
web of its own. It formed an attack upon a neighboring fortification
with great vigor, and at first was as vigorously repulsed. Not
daunted, however, with one defeat, in this manner it continued to lay
siege to another's web for three days, and at length, having killed
the defendant, actually took possession. When smaller flies happen to
fall into the snare, the spider does not sally out at once, but very
patiently waits till it is sure of them; for upon his immediately
approaching, the terror of his appearance might give the captive
strength sufficient to get loose; the manner then is to wait patiently
till by ineffectual and impotent struggles the captive has wasted all
its strength, and then it becomes a certain and easy conquest.
The insect I am now describing lived three years; every year it
changed its skin and got a new set of legs. I have sometimes plucked
off a leg, which grew again in two or three days. At first it dreaded
my approach to its web, but at last it became so familiar as to take a
fly out of my hand; and upon my touching any part of the web, would
immediately leave its hole, prepared either for a defense or an
attack.
To complete this description, it may be observed that the male spiders
are much less than the female, and that the latter are oviparous. When
they come to lay, they spread a part of their web under the eggs, and
then roll them up carefully, as we roll up things in a cloth, and thus
hatch them in their hole. If disturbed in their holes they never
attempt to escape without carrying this young brood, in their forceps,
away with them, and thus frequently are sacrificed to their paternal
affection.
As soon as ever the young ones leave their artificial covering, they
begin to spin, and almost sensibly seem to grow bigger. If they have
the good fortune, when even but a day old, to catch a fly, they fall
to with good appetites; but they live sometimes three or four days
without any sort of sustenance, and yet still continue to grow larger,
so as every day to double their former size. As they grow old,
however, they do not still continue to increase, but their legs only
continue to grow longer; and when a spider becomes entirely stiff with
age and unable to seize its prey, it dies at length of hunger.