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consequence of its physiological structure, of
assimilating a given amount of aliment, the more
effective force it will set at liberty, or, in other
words, the more strength it will have at its own
disposal. Now, the solar forces, thus rendered
active within the frame of a living creature,
have, by determining its growth, to construct
the animal itself. They have to generate its
own proper vitality, as well as the result of
vitality, its muscular power. It may therefore
be asserted that the effective force at the
disposal of every living creature will increase in
proportion to its alimentation, and will diminish
in proportion to its weight. Otherwise expressing
the same idea: The more food an animal
consumes and the less it weighs, the more
muscular strength it will possess.

These deductions have lately been confirmed
by curious experiments instituted by M. Felix
Plateau, who has determined the value of the
relative muscular power of insectspower of
pushing, power of drawing, and the weight
which the creature is able to fly away with.

It had already been remarked that animals of
small stature are by no means proportionally the
weakest. Pliny, in his Natural History, asserts
that, in strength, the ant is superior to all other
creatures. The length and height of the flea's
leap also appear quite out of proportion to its
weight. No very definite conclusion, however,
had hitherto been arrived at. M. Plateau has
settled the question by employing exact science
as the test. Insects belonging to different
species, placed on a plane surface, have been
made to draw gradually increasing weights.

A man of thirty, weighing on an average a
hundred and thirty pounds, can drag, according
to Regnier, only a hundred and twenty pounds.
The proportion of the weight drawn to the
weight of his body is no more than as twelve to
thirteen. A draught-horse can exert, only for a
few instants, an effort equal to about two-thirds
of his own proper weight. The man, therefore,
is stronger than the horse.

But, according to M. Plateau, the smallest
insect drags without difficulty five, six, ten,
twenty times its own weight, and more. The
cockchafer draws fourteen times its own weight.
Other coleoptera are able to put themselves into
equilibrium with a force of traction reaching as
high as forty-two times their own weight.
Insects, therefore, when compared with the
vertebrata which we employ as beasts of draught,
have enormous muscular power. If a horse
had the same relative strength as a donacia, the
traction it could exercise would be equivalent to
some sixty thousand pounds.

M. Plateau has also adduced evidence of the
fact that, in the same group of insects, if you
compare two insects notably differing in weight, the
smallest and lightest will manifest the greatest
strength.

To ascertain its pushing power, M. Plateau
introduced the insect into a card-paper tube
whose inner surface had been slightly roughened.
The creature, perceiving the light at the end
through a transparent plate which barred its
passage, advanced by pushing the latter forward
with all its might and main, especially if
excited a little. The plate, pushed forward, acted
on a lever connected with an apparatus for
measuring the effort made. In this case also
it turned out that the comparative power of
pushing, like that of traction, is greater in
proportion as the size and weight of the insect are
small. Experiments to determine the weight
which a flying insect can carry, were performed
by means of a thread with a ball of putty at the
end, whose mass could be augmented or reduced
at will. The result is that, during flight, an
insect cannot carry a weight sensibly greater
than that of its own body.

Consequently, man, less heavy than the horse,
has a greater relative muscular power. The dog,
less heavy than man, drags a comparatively
heavier burden. Insects, as their weight grows
less and less, are able to drag more and more.
It would appear, therefore, that the muscular
force of living creatures is in inverse proportion
to their mass.

But we must not forget that it ought to be in
direct proportion to the quantity of carbon
burnt in their system. To put the law
completely out of doubt, it would be necessary to
determine the exact weight of the food
consumed, and the quantity of carbonic acid
disengaged in the act of breathing. Some chemist
will settle it for us one of these days.

SALISBURY FORTY-FIVE YEARS AGO.

IT was a great sight to see Alderman Banks
prepare for his morning walk. The front door
opened, and the alderman appeared on his fair
white door-step exactly as the clock of Saint
Edmund's struck nine. No cuckoo on a German
clock was ever more punctual than the alderman.
He was a burly portly beaming sort of
man, an upholsterer by trade, with large shining
cheeks, a mammoth chest, and huge bedpost
legs. His presence indicated good nature, a
comfortable income, and much good feeding.
As Davis, the livery-stable-keeper, used to
professionally observe, " Alderman Banks do credit
to his keep." Our fellow-citizen wore a
low-crowned buttoned-up hat, such as bishops affect
in the present day; he also rejoiced in
claret-coloured and snuff-brown and bottle-green and
cinnamon coats, heavy and broad-napped,
knee-breeches, and buckled shoes.

His first proceeding was what we youngsters
used then to denominate " screwing on his
legs." The alderman's limbs, though stately
and unelastic, were neither of them of wood.
The ceremony consisted in a careful revolving
motion and adjustment of knee-breeches and
blue worsted stockings with the palms of both
hands, so that the knee-buckles should set
square and straight to the side, and the
stockings lie smooth and even over the calves of
the plump well-to-do legs. This operation
completed, the alderman would smile self-complacently,
stretch out both arms horizontally, and