fishing-rod and line, though it be told
circumstantially and on the authority of a bishop—the
learned Pontoppidan—of Norway. He
narrates how Reynard places himself on a stone at
the edge of a fiord, and drops his bushy tail in
the shallow brine. To it are attracted the crabs
which prowl among the pebbles and seaweed,
and, as they fasten their claws in his hair, the
cunning animal, by a sudden reversal of his
position, casts them out upon dry land, and
makes a capital breakfast.

Another narrative, which originated with
Dampier, and has the sanction of many
repetitions, we may brand as untrustworthy, while
we tell it for its excellence as an invention.
When certain monkeys of South America come,
in their woodland migrations, to a river too
wide to be taken at a leap, they seek a point
where two tall trees stand on the opposite
banks. Round the overhanging bough of one
the stoutest monkey coils his tail, and, thereby
pendent, head downward, grasps in his paws the
tail of monkey number two. The latter does
the same by monkey number three, and so on,
till a pendent chain is formed, when they begin
to swing in longer and longer sweeps until the
final monkey can catch, when at the end of his
arc of motion, a projecting limb of the opposite
tree. Then he climbs up until he has a good
point d'appui, and, monkey number one letting
go his hold of the first tree, the chain swings
across, and all scramble up each other in
reversed order, and go on their way rejoicing.

We should also at least suspend giving full
credence to the story how the rat makes of his
wiry appendix, on special occasions, a draught-
chain or tow-line. Yet we are assured that
once, in Scotland, a thrifty laird, finding his
store of eggs diminish, watched to see how the
thieves could carry them away. He saw three
rats go together to the pile of eggs, when, one
turning on his back, the others rolled an egg
upon him, which he clasped safely to his
bosom, and his companions, taking his tail
carefully in their mouths, started off like a team
drawing a sledge, and disappeared behind some
barrels which were the outer fortifications of
their castle.

Another story of rats' tails is more credible,
hovering on the verge between myth and sober
verity. This time it was a Frenchman, whose
oil wasted unaccountably, although the narrow
neck of his flask had seemed a sufficient security
against depredation. By a course of
espionage like that of the Scotchman, he
detected the rats lowering their tails alternately
into the flask, and drawing them up covered
with the luscious fluid, which each in turn
offered to his friend.

Leaving the skirts of fable-land, we find
enough of incontrovertible uses to which tails
are put. The fish's tail is his propeller, by
which the pike or the albacore darts like an
arrow through the water, and the salmon ascends
the fall. By its power the breaching whale
throws his huge bulk of a hundred tons clear out
from the brine, to fall in a surge and splash of
foam, visible from the whaler's deck at five miles'
distance; and, by its powerful strokes, the same
creature, when struck by the harpoon, dashes
off through the billows ten knots an hour, drawing
after him the boats filled with his
persecutors, half-drowned in spray. The sword-fish
attains by its use the velocity which has, in
repeated instances, driven his blade through the
copper and thick planking deep into the ship's
hold. The "propeller," as adapted to our
vessels, is nothing but a fish's tail, applied, for
mechanical convenience, with a rotary instead
of a reciprocating motion, just as a man, not
able easily to put under his railway-engine a set
of legs moving alternately like his own, modifies
the plan, and resorts to the contrivance of an
indefinite number of legs radiating from an
axle instead of a hip-joint, and, by rotating it,
brings them down successively in front of each
other, so that his machine walks or runs along
very well.

We have already mentioned the peculiar
arrangement of the tails of the old red-sandstone
and carboniferous fishes—an arrangement
perpetuated in our day only in a few existing
instances, such as the shark; though some others,
such as the gar or bony pike, which have a
nearly symmetrical tail when adult, have an
unequal or "heterocercal" one while young—an
arrangement which seems to show an analogy
between the general progress of created forms
and the successive stages in life of the growing
individual—of which, whoso would know more,
let him subscribe to Agassiz's new work, and
learn.

The form of fishes' tails are adapted to the
general forms of their owners, and suited for
the attainment of greater or less speed. The
cat-fish and other sluggish swimmers have
obtuse rounded tails. The swifter fishes, such
as the mackerel or shark, have the tail prolonged
into pointed lobes, "so that the area of the
surface of the tail is in the inverse ratio of the
distance from its axis of motion—the figure which
may be considered best adapted for great velocity
of progression." So say the learned. And
an entirely analogous feature may be observed in
the wings, which are the propelling organs of
birds. The slow and heavy-flying kinds, like
the gallinaceous tribe, having short and rounded
wings, while those of swift and long-continued
flight, as the swallows, gulls, and petrels, have
long and pointed wings. Experiments, suggested
by such observations, seem to show that pointed,
instead of broad and rectangular, paddles would
give greater velocity to steam-boats, were not
their use practically inconvenient.

The lobster-like crustacea also make their
tails instruments of progression, or rather, we
should say, of retrogression, for they flap them
violently forward under the body, and dart
backwards from the reaction of the stroke with an
arrow-like velocity, surprising to those who,
seeing these animals only on land, deem them
sluggish in their movements.

The swimming reptiles also make the tail
their main instrument of progression—at least,