The Fargo forum and daily republican., 1906-04-26
INSECT ENGINEERING
INTERESTINGL Y DESCRIBED

i Phin's Seven Follies of Science, d
Van Nostrand Co, publishers, New
York One of the most interesting
books in natural history is a work on
Insect Architecture, by Rennie. But if
architecture OF insect homes is wonder
Iful, the engineering displayed by these
Icreatures is equally anarvelous. Long
before man had thought of the saw, the
IsaW-fy had used the same tool. made
latter the same fashion, and used in the
same way for the purpose of making
Sits iii The branches of trees so that
she might have a secure place in which
to deposit her eggs. The carpenter bee,
with only the. tools which nature has
| given her cuts round hole, the full
i diameter of her body, through thick
boards, and SO makes tunnel BY which
to rear her young. The tunble-bug,
without derrick or machinery rolls over
large masses of dirt many times her
oWn weight, and the sexton beetle will,
lin afew hous, bury beneath the ground
1.-THE carcass of a comparatively large an
Emal All OF these feats require de-
Igree of instinct which in reasoning
|creature would be called engineering
Iskill, but none of them are as wonder
full as the feats performed by the spider.
i This extraordinary little animal has the
faculty of propelling her threads direct
lily against the wind, and by means of
iher slender cords she can haul up and
Isuspend bodies which are many times
lher own weight. r., #
4 Some years ago aparagraph went the
rounds of the papers in which it was
lsaid that a spider had suspended an un-
fortunate mouse, raising it up from the
lground, and leaving it to perish miser-
Iably between heaven and earth. Would
be philosophers made great fun of the
Statement, and ridiculed it numerically.
III know not how true it was, but
know that it might have been true.
i Some years ago, in the village of
Havana, in the State of New York, a
Ispider. entangled a milk-snake in her
Threads, and actually raised it some dis
tanceS from the ground, and this, too,
IN spite OF the struggles of the reptile,
(which was alive. ~. .,&I l,5 = :
i By what process of engineering did
1.-THE comparatively small and feeble in
Isect succeed in overcoming and lifting
Iup by mechanical means, the mouse or
the snake The solution is easy enough
lit we only give the question little
Thought. 49,
The spider is furnished with one OF
the most efficient mechanical implements
known to engineers, viz, a strong elias
tic thread That the thread is Strong
is we'll known. Indeed. there are few
II Net %l,ok
strain than the silk of the silkworm, or
1.-THE spider, careful experiment having
shown that for equal sizes the strength
Iof these fbres exceeds that of common
iron. But notwithstanding its strength,
the spiders thread alone would be use
less as mechanical power if it were
mot for its elasticity The spider has
no blocks Or pulley, and, therefore, it
/ cannot cause the thread to divide 'up
and run in different directions, but the
elasticity of the thread more than makes
up for this. and renders possible the
lifting of an animal much heavier than
"a mouse or a snake. This may require
a little explanation.
Il 4 Let us suppose that child can lift
Ia six-pour1d weight one foot high and
do this twenty times minute, Fur
lnish him with $50 rubber bands, each
Icapable of pulling six pounds through
one foot when stretched. Let these
bands be attached to a wooden plat
form on which stands pair of horses
Iweighing 2,Ioo pounds, or rather more
THAN a ton Ii now the child will go to
Iwork and stretch these rubber bands,
singly, hooking each one up. as it is
stretched, in less Than twenty minutes
he will have raised the pair Of horses
4 one footi @ W
We thus see that the elasticity of the
rubber bands enables the child to de-
lvide the weight of the horses into $50
lpieces of six pounds each, and at the
Irate of a little less than one every three
seconds, he lifts all these separate pieces
one foot. so that the child easily lifts
i this enormous weight.
/ Each spiders thread acts like one of
1.-THE elastic rubber bands. Let lis sup
pose that the mouse or. snake weighed
\ half am ounce and that each thread is
tcapable of supporting a grain and a
Ihalf. The spider would have to CON
Inect the mouse with the point from
| threads, and if the little quadruped was
I0IlCe swung OH Ills 4 siSCt, Ise WOltiu DC
Ipowerless. By pulling successively on
each thread and shortening it a little,
1.-THE mouse or snake might be raised to
any height within the capacity Of the
building OF structure in which the work
was done So that to those who have
ridiculed the story we may justly say !:
There are more things in heaven and
lsarth than are dreamed Of in your phil
osophy.
| What object the spider could have
had in his work / am unable to see. 1t
lmay have been dread of the harm
which the mouse or snake might work,
4 or ii may have been the hope that the
|decaying carcass would attract flies
(which would furnish food for the engi-
neer. can voucl for the truth of the
snake story, however, and the object of
this article IS TO explain and render
csedible d very extraordinary feat Of
Insect engineering.