Young Folks' Library, Volume XI (of 20) by Various

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[Illustration: THE MULE-CART.]

The mule-cart arrived; the lady of the party was put into it on a
chair, and slowly bumped and rattled past the corner of Dundonald
Street--so named after the old sea-hero, who was, in his life-time,
full of projects for utilizing this same pitch--and up in pitch road,
with a pitch gutter on each side.

The pitch in the road has been, most of it, laid down by hand, and is
slowly working down the slight incline, leaving pools and ruts full of
water, often invisible, because covered with a film of brown
pitch-dust, and so letting in the unwary walker over his shoes. The
pitch in the gutter-bank is in its native place, and as it spues
slowly out of the soil into the ditch in odd wreaths and lumps, we
could watch, in little, the process which has produced the whole
deposit--probably the whole lake itself.

A bullock-cart, laden with pitch, came jolting down past us, and we
observed that the lumps, when the fracture is fresh, have all a drawn
out look; that the very air bubbles in them, which are often very
numerous, are all drawn out likewise, long and oval, like the
air-bubbles in some ductile lavas.

On our left, as we went on, the bush was low, all of yellow cassia and
white Hibiscus, and tangled with lovely convolvulus-like creepers,
Ipomoea and Echites, with white, purple or yellow flowers. On the
right were negro huts and gardens, fewer and fewer as we went on,--all
rich with fruit trees, especially with oranges, hung with fruit of
every hue; and beneath them, of course, the pine-apples of La Brea.
Everywhere along the road grew, seemingly wild here, that pretty low
tree, Cashew, with rounded yellow-veined leaves and little green
flowers, followed by a quaint pink and red-striped pear, from which
hangs, at the larger and lower end, a kidney-shaped bean, which bold
folk eat when roasted; but woe to those who try it when raw; for the
acrid oil blisters the lips, and even while the beans are roasting the
fumes of the oil will blister the cook's face if she holds it too near
the fire.

As we went onward up the gentle slope (the rise is one hundred and
thirty-eight feet in rather more than a mile), the ground became more
and more full of pitch, and the vegetation poorer and more rushy,
till it resembled, on the whole, that of an English fen. An Ipomoea or
two, and a scarlet flowered dwarf Heliconia, kept up the tropic type,
as does a stiff brittle fern about two feet high. We picked the weeds,
which looked like English mint or basil, and found that most of them
had three longitudinal nerves in each leaf, and were really
Melastomas, though dwarfed into a far meaner habit than that of the
noble forms we saw at Chaguanas, and again on the other side of the
lake. On the right, too, in a hollow, was a whole wood of Groogroo
palms, gray stemmed, gray leaved, and here and there a patch of white
or black Roseau rose gracefully eight or ten feet high among the
reeds.

The plateau of pitch now widened out, and the whole ground looked like
an asphalt pavement, half overgrown with marsh-loving weeds, whose
roots feed in the sloppy water which overlies the pitch. But, as yet,
there was no sign of the lake. The incline, though gentle, shuts off
the view of what is beyond. This last lip of the lake has surely
overflowed, and is overflowing still, though very slowly. Its furrows
all curve downward; and it is, in fact, as one of our party said, "a
black glacier." The pitch, expanding under the burning sun of day,
must needs expand most toward the line of least resistance--that is,
downhill; and when it contracts again under the coolness of night, it
contracts, surely, from the same cause, more downhill than uphill; and
so each particle never returns to the spot whence it started, but
rather drags the particles above it downward toward itself. At least,
so it seemed to us. Thus may be explained the common mistake which is
noticed by Messrs. Wall and Sawkins in their admirable description of
the lake.

"All previous descriptions refer the bituminous matter scattered over
the La Brea district, and especially that between the village and the
lake, to streams which have issued at some former epoch from the lake,
and extended into the sea. This supposition is totally incorrect, as
solidification would probably have ensued before it had proceeded
one-tenth of the distance; and such of the asphalt as has undoubtedly
escaped from the lake has not advanced more than a few yards, and
always presents the curved surfaces already described, and never
appears as an extended sheet."

Agreeing with this statement as a whole, I nevertheless cannot but
think it probable that a great deal of the asphalt, whether it be in
large masses or in scattered veins, may be moving very slowly down
hill, from the lake to the sea, by the process of expansion by day and
contraction by night, and may be likened to a caterpillar, or rather
caterpillars innumerable, progressing by expanding and contracting
their rings, having strength enough to crawl down hill, but not
strength enough to back up hill again.

At last we surmounted the last rise, and before us lay the famous
lake--not at the bottom of a depression, as we expected, but at the
top of a rise, whence the ground slopes away from it on two sides, and
rises from it very slightly on the two others. The black pool glared
and glittered in the sun. A group of islands, some twenty yards wide,
were scattered about the middle of it. Beyond it rose a double forest
of Moriche fan-palms; and to the right of them high wood with giant
Mombins and undergrowth of Cocorite--a paradise on the other side of
the Stygian pool.

[Illustration: THE PITCH LAKE.]

We walked, with some misgivings, on to the asphalt, and found it
perfectly hard. In a few steps we were stopped by a channel of clear
water, with tiny fish and water-beetles in it; and, looking round, saw
that the whole lake was intersected with channels, so unlike anything
which can be seen elsewhere that it is not easy to describe them.

Conceive a crowd of mushrooms, of all shapes, from ten to fifty feet
across, close together side by side, their tops being kept at exactly
the same level, their rounded rims squeezed tight against each other;
then conceive water poured on them so as to fill the parting seams,
and in the wet season, during which we visited it, to overflow the
tops somewhat. Thus would each mushroom represent, tolerably well, one
of the innumerable flat asphalt bosses, which seem to have sprung up
each from a separate centre, while the parting seams would be of much
the same shape as those in the asphalt, broad and shallow atop, and
rolling downward in a smooth curve, till they are at bottom mere
cracks from two to ten feet deep. Whether these cracks actually close
up below, and the two contiguous masses of pitch become one, cannot be
seen. As far as the eye goes down, they are two, though pressed close
to each other. Messrs. Wall and Sawkins explain the odd fact clearly
and simply. The oil, they say, which the asphalt contains when it
rises first, evaporates in the sun, of course most on the outside of
the heap, leaving a thorough coat of asphalt, which has, generally, no
power to unite with the corresponding coat of the next mass. Meanwhile
Mr. Manross, an American gentleman, who has written a very clever and
interesting account of the lake, seems to have been so far deceived by
the curved and squeezed edges of these masses that he attributes to
each of them a revolving motion, and supposes that the material is
continually passing from the centre to the edges, when it "rolls
under," and rises again in the middle. Certainly the strange stuff
looks, at the first glance, as if it were behaving in this way; and
certainly, also, his theory would explain the appearance of sticks and
logs in the pitch. But Messrs. Wall and Sawkins say that they have
observed no such motion: nor did we; and I agree with them, that it is
not very obvious to what force, or what influence, it could be
attributable. We must, therefore, seek some other way of accounting
for the sticks--which utterly puzzled us, and which Mr. Manross well
describes as "numerous pieces of wood, which, being involved in the
pitch, are constantly coming to the surface. They are often several
feet in length, and five or six inches in diameter. On reaching the
surface they generally assume an upright position, one end being
detained in the pitch, while the other is elevated by the lifting of
the middle. They may be seen at frequent intervals over the lake,
standing up to the height of two or even three feet. They look like
stumps of trees protruding through the pitch; but their parvenu
character is curiously betrayed by a ragged cap of pitch which
invariably covers the top, and hangs down like hounds' ears on either
side."

Whence do they come? Have they been blown on to the lake, or left
behind by man? or are they fossil trees, integral parts of the
vegetable stratum below which is continually rolling upward? or are
they of both kinds? I do not know. Only this is certain, as Messrs.
Wall and Sawkins have pointed out, that not only "the purer varieties
of asphalt, such as approach or are identical with asphalt glance,
have been observed" (though not, I think, in the lake itself) "in
isolated masses, where there was little doubt of their proceeding from
ligneous substances of larger dimensions, such as roots and pieces of
trunks and branches," but, moreover, that "it is also necessary to
admit a species of conversion by contact, since pieces of wood
included accidentally in the asphalt, for example, by dropping from
overhanging vegetation, are often found partially transformed into the
material." This is a statement which we verified again and again, as
we did the one which follows, namely, that the hollow bubbles which
abound on the surface of the pitch "generally contain traces of the
lighter portion of vegetation," and "are manifestly derived from
leaves, etc., which are blown about the lake by the wind, and are
covered with asphalt, and, as they become asphalt themselves, give off
gases which form bubbles round them."

But how is it that those logs stand up out of the asphalt, with
asphalt caps and hounds' ears (as Mr. Manross well phrases it) on the
tops of them?

We pushed on across the lake, over the planks which the negroes laid
down from island to island. Some, meanwhile, preferred a steeple-chase
with water-jumps, after the fashion of the midshipmen on a certain
second visit to the lake. How the negroes grinned delight and surprise
at the vagaries of English lads--a species of animal altogether new to
them; and how they grinned still more when certain staid and portly
dignitaries caught the infection, and proved by more than one good
leap that they too had been English school-boys--alas! long, long ago.

So, whether by bridging, leaping, or wading, we arrived at the little
islands, and found them covered with a thick, low scrub; deep sedge,
and among them Pinguins, like huge pine-apples without the apple; gray
wild-pines, parasites on Matapalos, which, of course, have established
themselves, like robbers and vagrants as they are, everywhere; a true
holly, with box-like leaves; and a rare cocoa-plum, very like the
holly in habit, which seems to be all but confined to these little
patches of red earth, afloat on the pitch. Out of the scrub, when we
were there, flew off two or three night-jars, very like our English
species, save that they had white in the wings; and on the second
visit one of the midshipmen, true to the English boy's bird's-nesting
instinct, found one of their eggs, white-spotted, in a grass nest.

Passing these little islands, which are said (I know not how truly) to
change their places and number, we came to the very fountains of Styx,
to that part of the lake where the asphalt is still oozing up.

As the wind set toward us, we soon became aware of an evil
smell--petroleum and sulphureted hydrogen at once--which gave some of
us a headache. The pitch here is yellow and white with sulphur foam;
so are the water-channels; and out of both water and pitch innumerable
bubbles of gas arise, loathsome to the smell. We became aware that the
pitch was soft under our feet. We left the impression of our boots;
and if we had stood still awhile, we should soon have been ankle-deep.
No doubt there are spots where, if a man stayed long enough, he would
be slowly and horribly engulfed. "But," as Mr. Manross says truly, "in
no place is it possible to form those bowl-like depressions round the
observer described by former travellers." What we did see is that the
fresh pitch oozes out at the lines of least resistance, namely, in the
channels between the older and more hardened masses, usually at the
upper ends of them, so that one may stand on pitch comparatively hard,
and put one's hand into pitch quite liquid, which is flowing softly
out, like some ugly fungoid growth, such as may be seen in old
wine-cellars, into the water. One such pitch-fungus had grown several
yards in length in the three weeks between our first and second visit;
and on another, some of our party performed exactly the same feat as
Mr. Manross.

"In one of the star-shaped pools of water, some five feet deep, a
column of pitch had been forced perpendicularly up from the bottom. On
reaching the surface of the water it had formed a sort of
centre-table, about four feet in diameter, but without touching the
sides of the pool. The stem was about a foot in diameter. I leaped out
on this table, and found that it not only sustained my weight, but
that the elasticity of the stem enabled me to rock it from side to
side. Pieces torn from the edges of this table sank readily, showing
that it had been raised by pressure, and not by its buoyancy."

True, though strange; but stranger still did it seem to us when we did
at last what the negroes asked us, and dipped our hands into the
liquid pitch, to find that it did not soil the fingers. The old
proverb that one cannot touch pitch without being defiled happily does
not stand true here, or the place would be intolerably loathsome. It
can be scraped up, moulded into any shape you will, wound in a string
(as was done by one of the midshipmen) round a stick, and carried off;
but nothing is left on the hand save clean gray mud and water. It may
be kneaded for an hour before the mud be sufficiently driven out of it
to make it sticky. This very abundance of earthy matter it is which,
while it keeps the pitch from soiling, makes it far less valuable than
it would be were it pure.

It is easy to understand whence this earthy matter (twenty or thirty
per cent) comes. Throughout the neighborhood the ground is full, to
the depth of hundreds of feet, of coaly and asphaltic matter. Layers
of sandstone or of shale containing this decayed vegetable alternate
with layers which contain none; and if, as seems probable, the coaly
matter is continually changing into asphalt and oil, and then working
its way upward through every crack and pore, to escape from the
enormous pressure of the superincumbent soil, it must needs carry up
with it innumerable particles of the soils through which it passes.

In five minutes we had seen, handled, and smelt enough to satisfy us
with this very odd and very nasty vagary of tropic nature; and as we
did not wish to become faint and ill between the sulphureted hydrogen
and the blaze of the sun reflected off the hot black pitch, we hurried
on over the water-furrows, and through the sedge-beds to the farther
shore--to find ourselves, in a single step, out of an Inferno into a
Paradise.

[Illustration]

A STALAGMITE CAVE

(FROM THE VOYAGE OF THE CHALLENGER.)

BY SIR C. WYVILLE THOMSON, KT., LL.D., ETC.

[Illustration]

I think the Painter's Vale cave is the prettiest of the whole. The
opening is not very large. It is an arch over a great mass of debris
forming a steep slope into the cave, as if part of the roof of the
vault had suddenly fallen in. At the foot of the bank of debris one
can barely see in the dim light the deep clear water lying perfectly
still and reflecting the roof and margin like a mirror. We clambered
down the slope, and as the eye became more accustomed to the obscurity
the lake stretched further back. There was a crazy little punt moored
to the shore, and after lighting candles Captain Nares rowed the
Governor back into the darkness, the candles throwing a dim light for
a time--while the voices became more hollow and distant--upon the
surface of the water and the vault of stalactite, and finally passing
back as mere specks into the silence.

[Illustration: A GUIDE.]

After landing the Governor on the opposite side, Captain Nares
returned for me, and we rowed round the weird little lake. It was
certainly very curious and beautiful; evidently a huge cavity out of
which the calcareous sand had been washed or dissolved, and whose
walls, still to a certain extent permeable, had been hardened and
petrified by the constant percolation of water charged with carbonate
of lime. From the roof innumerable stalactites, perfectly white, often
several yards long and coming down to the delicacy of knitting-needles,
hung in clusters; and wherever there was any continuous crack in the
roof or wall, a graceful, soft-looking curtain of white stalactite
fell, and often ended, much to our surprise. Deep in the water
Stalagmites also rose up in pinnacles and fringes through the water,
which was so exquisitely still and clear that it was something
difficult to tell where the solid marble tracery ended, and its
reflected image began. In this cave, which is a considerable distance
from the sea, there is a slight change of level with the tide
sufficient to keep the water perfectly pure. The mouth of the cave is
overgrown with foliage, and every tree is draped and festooned with
the fragrant _Jasminum gracile_, mingled not unfrequently with the
"poison ivy" (_Rhus toxicodendron_). The Bermudians, especially the
dark people, have a most exaggerated horror of this bush. They imagine
that if one touch it or rub against it he becomes feverish, and is
covered with an eruption. This is no doubt entirely mythical. The
plant is very poisonous, but the perfume of the flower is rather
agreeable, and we constantly plucked and smelt it without its
producing any unpleasant effect. The tide was with us when we regained
the Flats Bridge, and the galley shot down the rapid like an arrow,
the beds of scarlet sponges and the great lazy trepangs showing
perfectly clearly on the bottom at a fathom depth.

[Illustration: FIG. 1. CALCAREOUS CONCRETION SIMULATING A FOSSIL
PALM-STEM, BOAZ ISLAND, BERMUDAS.]

Every here and there throughout the islands there are groups of bodies
of very peculiar form projecting from the surface of the limestone
where it has been weathered. These have usually been regarded as
fossil palmetto stumps, the roots of trees which have been overwhelmed
with sand and whose organic matter has been entirely removed and
replaced by carbonate of lime. Fig. 1 represents one of the most
characteristic of these from a group on the side of the road in Boaz
Island. It is a cylinder a foot in diameter and six inches or so high;
the upper surface forms a shallow depression an inch deep surrounded
by a raised border; the bottom of the cup is even, and pitted over
with small depressions like the marks of rain-drops on sand; the walls
of the cylinder seem to end a few inches below the surface of the
limestone in a rounded boss, and all over this there are round
markings or little cylindrical projections like the origins of
rootlets. The object certainly appears to agree even in every detail
with a fossil palm-root, and as the palmetto is abundant on the
islands and is constantly liable to be destroyed by and ultimately
enveloped in a mass of moving sand, it seemed almost unreasonable to
question its being one. Still something about the look of these things
made me doubt, with General Nelson, whether they were fossil palms, or
indeed whether they were of organic origin at all; and after carefully
examining and pondering over several groups of them, at Boaz Island,
on the shore at Mount Langton, and elsewhere, I finally came to the
conclusion that they were not fossils, but something totally
different.

[Illustration: FIG. 2. CALCAREOUS CONCRETION IN AEOLIAN LIMESTONE,
BERMUDAS.]

[Illustration: FIG. 3. CALCAREOUS CONCRETION IN AEOLIAN LIMESTONE,
BERMUDAS.]

[Illustration: FIG. 4. CALCAREOUS CONCRETION, BERMUDAS.]

[Illustration: FIG. 5. CALCAREOUS CONCRETION IN AEOLIAN LIMESTONE,
BERMUDAS.]

The form given in Fig. 1 is the most characteristic, and probably by
far the most common; but very frequently one of a group of these, one
which is evidently essentially the same as the rest and formed in the
same way, has an oval or an irregular shape (Figs. 2, 3, and 4). In
these we have the same raised border, the same scars on the outside,
the same origins of root-like fibres, and the same pitting of the
bottom of the shallow cup; but their form precludes the possibility of
their being tree-roots. In some cases (Fig. 5), a group of so-called
"palm-stems" is inclosed in a space surrounded by a ridge, and on
examining it closely this outer ridge is found to show the same
leaf-scars and traces of rootlets as the "palm-stems" themselves. In
some cases very irregular honey-combed figures are produced which the
examination of a long series of intermediate forms shows to belong to
the same category (Fig. 6).

[Illustration: FIG. 6. CONCRETIONS IN AEOLIAN ROCKS, BERMUDAS.]

In the caves in the limestone, owing to a thread of water having found
its way in a particular direction through the porous stone of the
roof, a drop falls age after age on one spot on the cave-floor,
accurately directed by the stalactite which it is all the time
creating. The water contains a certain proportion of carbonate of
lime, which is deposited as stalagmite as the water evaporates, and
thus a ring-like crust is produced at a little distance from the spot
where the drop falls. When a ring is once formed, it limits the spread
of the drop, and determines the position of the wall bounding the
little pool made by the drop. The floor of the cave gradually rises by
the accumulation of sand and travertine, and with it rise the walls
and floor of the cup by the deposit of successive layers of stalagmite
produced by the drop percolating into the limestone of the floor which
hardens it still further, but in this peculiar symmetrical way. From
the floor and sides of the cup the water oozes into the softer
limestone around and beneath; but, as in all these limestones, it does
not ooze indiscriminately, but follows certain more free paths. These
become soon lined and finally blocked with stalagmite, and it is
these tubes and threads of stalagmite which afterwards in the
pseudo-fossil represent the diverging rootlets.

[Illustration: A STALAGMITE CAVE.]

Sometimes when two or more drops fall from stalactites close to one
another the cups coalesce (Figs. 2, 3, and 4); sometimes one drop or
two is more frequent than the other, and then we have the form shown
in Figs. 3 and 4; sometimes many drops irregularly scattered form a
large pool with its raised border, and a few drops more frequent and
more constant than the rest grow their "palmetto stems" within its
limit (Fig. 5); and sometimes a number of drops near one another make
a curious regular pattern, with the partitions between the recesses
quite straight (Fig. 6).

I have already referred to the rapid denudation which is going on in
these islands, and to the extent to which they have been denuded
within comparatively recent times. The floors of caves, from their
being cemented into a nearly homogeneous mass by stalagmitic matter,
are much harder than the ordinary porous blown limestone; and it seems
that in many cases, after the rocks forming the walls and roof have
been removed, disintegration has been at all events temporarily
arrested by the floor. Where there is a flat surface of rock exposed
anywhere on the island, it very generally bears traces of having been
at one time the floor of a cave; and as the weather-wearing of the
surface goes on, the old concretionary structures are gradually
brought out again, the parts specially hardened by a localized slow
infiltration of lime resist integration longest and project above the
general surface. Often a surface of weathered rock is so studded with
these symmetrical concretions, that it is hard to believe that one is
not looking at the calcified stumps of a close-growing grove of palms.

[Illustration]

THE BIG TREES OF CALIFORNIA

(FROM STUDIES SCIENTIFIC AND SOCIAL.)

BY ALFRED RUSSEL WALLACE.

[Illustration]

In the popular accounts of these trees it is usual to dwell only on
the dimensions of the very largest known specimens, and sometimes even
to exaggerate these. Even the smaller full-grown trees, however, are
of grand dimensions, varying from fourteen to eighteen feet in
diameter, at six feet above the ground, and keeping nearly the same
thickness for perhaps a hundred feet. In the south Calaveras grove,
where there are more than a thousand trees, the exquisite beauty of
the trunks is well displayed by the numerous specimens in perfect
health and vigor. The bark of these trees, seen at a little distance,
is of a bright orange brown tint, delicately mottled with darker
shades, and with a curious silky or plush-like gloss, which gives them
a richness of color far beyond that of any other conifer. The tree
which was cut down soon after the first discovery of the species, the
stump of which is now covered with a pavilion, is twenty-five feet in
diameter at six feet above the ground, but this is without the thick
bark, which would bring it to twenty-seven feet when alive. A
considerable portion of this tree still lies where it fell, and at one
hundred and thirty feet from the base I found it to be still twelve
and a half feet in diameter (or fourteen feet with the bark), while at
the extremity of the last piece remaining, two hundred and fifteen
feet from its base, it is six feet in diameter, or at least seven feet
with the bark. The height of this tree when it was cut down is not
recorded, but as one of the living trees is more than three hundred
and sixty feet high, it is probable that this giant was not much short
of four hundred feet.

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