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[page 49:]
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A CHAPTER ON SCIENCE AND ART.
————
ON THE EXPANSION
OF AIR IN ANIMAL BODIES
AND ITS EFFECTS IN A PARTICULAR
INSTANCE. — It is found that any animal when
dead,
being exposed to the air, is in a certain time wholly incorporated with
it. This fact is proved in a very striking manner, by an extraordinary
effect produced by those dead bodies, after they became filled with
air,
which were unfortunately drowned in the Royal George ship of war, at
Spithead,
on the 29th of August, 1782. This ship was heeled on her side for the
purpose
of some repair, when on a sudden a [[and]] violent gust of wind struck
her, the water rushed into her lower port-holes, and sunk her almost
instantaneously.
She went down in 14 fathoms [[of]] water, and fell upon her side, as
was
evident from the topmasts which remained above water, in an inclined
direction.
A considerable time after the fatal accident, she suddenly righted, and
her masts became perpendicular. No one could account for this
extraordinary
transaction, which was effected without any apparent cause; and it
remained
for some time a circumstance equally astonishing and inexplicable. The
following solution, however, may not be unsatisfactory. By the
muster-roll
of this unfortunate ship, which floated out of her cabin, and was
afterwards
taken up, it appears that at least 495 souls must have perished between
decks, being at their last dinner at the time she upset. As the bodies
had no way to escape, they, of course, remained in that situation. Now,
all bodies in a state of putrefaction, ferment, and this fermentation,
generates large quantities of air; so that a putrefying carcase
inflated
by the generation of air, expands itself to a size far exceeding its
original
bulk, and becomes lighter than water in a very high degree, and will
consequently
be pressed upwards towards the surface with a power equal to the weight
of a quantity of water adequate in bulk to the inflated carcase, and
would
rise immediately to the surface in a perpendicular line, if not
obstructed
in its passage. Thus it is obvious that the 495 carcases which lay
between
the decks until fermentation and putrefaction commenced, would rise as
soon as the generated air rendered them specifically lighter than sea
water;
and as fermentation increased their bulk, they would, by their
expansion,
remove a quantity of water from between the decks, on the lowest side
of
the ship (to which by their gravity they would naturally incline when
their
breath first left them) equal to their increased bulk; and being then
acted
upon by the upward pressure of the water, would ascend against the
under
part of the decks, immediately over them, a power likewise equal to
such
weight of water as equals their increased bulk. The heaviest side of
the
ship, being thus first lightened by the displacing [[of]] so large a
quantity
of water, and exchanging it for air, and then acted upon by the
pressure
of the water upwards against the under side of the inflated carcasses,
lifting hard against the decks, on or beneath the centre of the ship;
and,
farther, by the pressure of the water upwards against the under part of
the hull, masts, yards, &c., together with the counterpoise of a
large
weight of water between decks, on the highest side, would cause her to
be nearly in equilibrio, and, consequently, the first strong tide, as
was
the case, would swing her on her keel and right her. To show that 495
bloated
carcases might have power sufficient to produce so strange a
phenomenon,
let us suppose each carcase at that time equal to a twenty gallon cask,
and it could be no less, for, when in a state of putrefaction, not only
the abdomen, but even the smallest vessel in the human frame, becomes
inflated
by the vapors generated in fermentation; so that the limbs swell to the
extremities, and become buoyant, which makes the estimate of twenty
gallons
per carcase less perhaps than the truth. Then 495 (the number of
carcases
that remained between the decks,) being multiplied by 20, the number of
gallons increased in each carcase, which divided by 252, (the number of
gallons contained in a ton, liquid measure,) quote 39 tons 72 gallons,
which multiplied by 3, to answer the treble power, makes 118 tons
nearly,
a difference of weight between the two sides fully sufficient, with the
assistance of a spring-tide, to life the ship to balance, which the
tide,
though ever so strong, could not have effected without it. There were
nearly
200 persons floated from her decks when the ship went down, many of
whom
were drowned, some, however, were saved; and among others two or three
children, who being near some sheep on deck, caught hold of their
fleeces
and were carried safely on shore. The ship was afterwards thoroughly
explored
by means of a diving bell. Admiral Kempenfeldt was found sitting in his
cabin, with a pen in his hands, as if busily engaged in writing. The
Royal
George never could be raised, after many attempts so to do, and there
is
now a considerable shoal, it is said, formed around her.
———
The Linden tree is frequent in all
the northern and
middle states of American, and is in grateful use as a shade tree in
several
of the principal cities — but we doubt if our fellow citizens are
acquainted
with its excellence in various purposes as detailed in the following
extract
from a Scotch paper — we recommend its perusal to our country readers:
Of ever other tree connected with
rural economy,
perhaps the linden is the most valuable. In [page 50:]
Russia, its properties are so well understood that it is seen growing
in
every hamlet and village possessing a soil capable of nourishing it.
The
wood is not only manufactured into furniture, but into a variety of
domestic
utensils. Cords and matting are made from its inner rind, while its
aromatic
blossoms not only perfume the air and feed the bees, but make an
agreeable
ptisan for the invalid. The Circassians feed their bees on the
blossoms,
to produce the fine, green honey, aromatic in odor and delicious in
flavor,
esteemed so great a delicacy by the rich gourmands of Constantinople
and
Teheran. The young and tender sprigs, with their foliage, serve to mix
with fodder during the depth of winter, being highly palatable to the
cattle.
It is an ornamental tree, and may be seen adorning nearly every public
garden and promenade in Germany.
———
THE QUINQUINA
TREE. — Loxa, or Loja, which is
pronounced
with a guttural aspiration familiar to the Spanish language, is a small
town built by Mercadillo, one of Gonzales Pizarro's captains, [[about]]
1546, in an agreeable valley, on the river Catamayo. The meridian
altitudes
of the sun, give its latitude four degrees and almost one minute south,
that is, near seventy leagues south of Quito; being under the same
meridian
nearly, and about eighty leagues from the coast of Peru. Its elevation
is a mean between that of the mountains which form the vast chain of
the
Andes, and the valleys of the coast. The quicksilver stood at Loxa at
twenty-one
inches eight lines, whence it may be concluded, on comparing several
experiments,
that Loxa is about eight hundred toises above the level of the sea. The
climate is very pleasant, and the heats are indeed great, but not
excessive.
The best quinquina, at least that of
most repute,
is found on the mountain of Cajanuma, about two leagues and a half to
the
south of Loxa; and from thence came the first that was carried to
Europe.
Within these sixty years, the dealers have obtained a certificate from
a notary, that their quinquina is of the growth of Cajanuma.
The quinquina tree never grows on
plains; it rises
straight, and may be seen at a great distance above the tops of other
trees
about it; for it is never found in groves, but single, and scattered up
and down among others of various sorts. If they are permitted to stand,
they grow very large, sometimes larger than a man's body. The middle
size
are eight or nine inches in diameter; but it is now rare to find them
of
these dimensions upon the mountain. The trees from whence the first
bark
was taken, which were very large, are all dead, having been entirely
stripped,
which infallibly kills them when they come to be old. Experience has
shown,
that stripping kills some of the young ones also, but the greatest part
escape. For this operation, they use a common knife, which they hold in
both hands; the barker sticks it into the bark as high as he can reach,
and so draws it downwards as low as he can. It does not appear that the
trees which grow where the old ones stood, have less virtue, the
situation
and soil being the same. The difference, if there be any, may arise,
perhaps,
from the different ages of the trees. Few but young ones are now to be
met with.
At Loxa, heretofore, they have
preferred the coarsest
bark, and laid it by as a rarity; but now the finest is most esteemed.
The merchants may possibly find their account in it, as it takes less
room
in packing. Formerly, a director of the English South Sea Company at
Panama,
through whom all the quinquina that used to go to Europe passed,
asserted
that the preference given to the fine bark was in consequence of
several
chemical analyses and experiments which had been made on both sorts in
England. It seems probably, that the difficulty of throughly drying the
large coarse bard, and the humidity it is naturally apt to contract and
retain, contributed to bring it into disrepute. Vulgar prejudice will
have
it, that to lose nothing of its virtue, the tree should be barked in
the
moon's decrease, and on the east side. These circumstances, as also its
being fathered on the mountain of Cajanuma, were certified by a notary
in 1735, when the Marquis de Castelfuerte procured a quantity of
quinquina
from Loxa, to carry to Spain on his return.
But for the sake of not being idle
three-quarters
of the year, this prejudice was pretty well got over; and all seasons
of
the year are found equally proper, provided the weather is dry. The
bark,
after taking it away, should be exposed to the sun several days
together,
and for its better preservation, should not be packed till it has lost
all its humidity; and this is an essential circumstance. It is not
uncommon,
for want of this precaution before the packing, to find it mouldy, and
then the merchants are apt to lay the fault upon the moon, rather than
upon the negligence of those who did not dry it.
The leaves are fixed to a stem about
half an inch
long; they are smooth, and of a fine green, which is deep on the upper
side, and bright beneath. Their outline is even, and of the shape of a
lance, being rounded at bottom, and terminating in a point; they are,
for
the most part, an inch and a half or two inches broad, and two and a
half
or three inches long. |
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