Public ledger. [volume] (Memphis, Tenn.) 1865-1893, 1873-05-02

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examples show TO what an extent insects
are superior to the larger animals in the
strength of their muscles. Dry and
nervous, they can, in proportion 70 them
selves, move mountains. In addition 10
this, they are ingenious; when an object
does not yield to them, they know how
to turn il aside. One day, in a garden.
small wasp was trying TO raise a cater
pillar, which il had killed. The cater
pillar was at least five or six times heav-
ier than its eonqueror, which could not
gain ITS end. Six. times snccessiyely,
weary OF the war, and despairing Il sue
cess, it abandoned its prey, aud sadly
placed itself at some distance At last
a bright idea saved it from its embarrass-
ment; il turned, placed itself across the
caterpillar, as il on horseback; with it's
two middle feet it embraced the body Of
its victim, raised it against its breast
and managed to walk on the four feet
which were at liberty; thus it soon
crossed a walk of six feet wide, and laid
its prey against wall.
Investigations have been made re-
garding
THE JUMPING INSECTS H..
Of the order 0rthoptera, the weight which
crickets aud grasshoppers can raise
when jumping. To prevent them using
their wings, M. Plateau tied them and
the elytra or outer sheaths with thread.
The burden was ball OF wax ballasted
with morsels of lead, which was hung
to thread tied around the thorax; as
much lead was added TO the wax until
the insect could only raise itself an inch
from the ground. The ball and the in
sect were aiterward weighed, the latter
having been made insensible by the
fumes Of ether Oriehets of the larger
kind raised about one and a half their
own weight; the smaller ones, three or
four times their weight The grasshop-
per differs from the cricket in having
longer and thinner legs; the green va
riety, weighing about two and a half
grammes, can only raise weight equal
TO its own, confirming the law that the
muscular force of insects increases as
their size diminishes. When allowed to
jump freely, crickets describe a curve in
the air similar to all projectiles. 1t is
curious that the amplitude of the spring
is the same for the large and smaller
kinds alike. This result was foreseen
BY the celebrated naturalist, Strauss
Durckheim. In his work on The
Comparative Anatomy of Articulated
Animals" he establishes the point that
two animals of similar form, but of differ
ent dimensions, will jump the same hight
above the point where lies their center of
gravity at the moment when they quit
the soil. He takes az an example the
cat and the tiger and adds that the same
conclusion is applicable to crickets and
grasshoppers. The principle which
serves as basis for this theory is that
the motive-power of animals increases
with the section, and not the volume of
the muscles. 1t depends only on the
number of fbres of which the muscles
are composed; from whence it. follows
that it ought to be in proportion to the
surface of the section of these organs,
whilst the weight of the animal is pro-
portional to their volume. The weight
augments more rapidly than the motive
power, and the relation between this
weight and this force becomes the more
unfayorable as the animal is larger.
Other naturalists who agree to this as
whole do not consider it to be an absolute
or general law.
AMONG THE INSECTS THAT DIG l
or burrow in the ground, different plan
was tried to see their power of pushing
forward. They were placed in card
board tube, which had been blackened
and made rough for the feet; at one end
transparent plate of glass was fixed to
a horizontal lever. Perceiving the light.
before it through the plate which barred
its exit, the insect then excited pushes
with all its strength; the plate gives way,
the lever turns and raises at its other
extremity the balance, whichis attached
by a pulley, and into which the sand is
poured as before. In this way the
oryctes, weighing about forty-six grains,
pushed three or feur times its own
weight, whilst the little onthopagus
moved from eighty to ninety times that
amount. fe Sd n.
The experiments in the way of flying
lead to the conclusion that insects em=
ploy much less MUSCULAR force in that
way than in drawing or pushing; per-
haps it is that, unlike birds, they are not
intended to carry large weights through
the air. A ball of soft wax of a weight
little superior to what the insect might
be expected to bear, was fastened round
;ts hody, and it was tried as to whether
il could support this in the air; if it fell,
tbe s;ze was diminished. Among vari-
ous insects belonging to the five orders
of Cleoptera (beetles), it was found that
they could raise from one'sixth to don-
Bile their own weight the common fly
could manage triple that amount. let
the fight of insects is so rapid that some
can distance the swallows that pursue
them. and certain kinds Of flies are said
to be able TO pass race horse or loco
motive going at full speed.
If we INQUIRE why the smaller species
are the stronger, the answer may be, |
that their way Of life neeessitates il.
Tbas. the hardness of the soil is the
sar,e TO all tbs kgrrowers; the grain OF
sand which the larger can easily dispiAee
are rocks 10 the smaller ones apq CON-
pairing thea With animals, the mole and |
the rabbit require much less strength 70 I
force passage than the ant. The pro- |
digious leaps of the cricket the locust,
aud the grasshOpper, would 10 tne sane ,s 4
proportion make lion spring over haii
= mile. Not less surprie.-s :: the power
Of destruction in certain classes the |
termites have undermined WHOLE towns
which are nov suspended over cata-
combs; such is the case with Valencia |
in New Granada; La hO0hslle Is me-
nacsd By the same fate. The lave Of
the sireK pierce through balls OF lead
with their msndibles. During the Cri- !
mean war, packets Of cartouches were
found, the conical balls Of vhich we're
perforated in various parts. The little |
A lriann ant can rnian mnunlE nl clay