The Voyage Of The Beagle

Chapter XI

 

(PLATE 50. WOLLASTON ISLAND, TIERRA DEL FUEGO.)

(PLATE 51. PATAGONIANS FROM CAPE GREGORY.)

Strait of Magellan.
Port Famine.
Ascent of Mount Tarn.
Forests.
Edible fungus.
Zoology.
Great Seaweed.
Leave Tierra del Fuego.
Climate.
Fruit-trees and productions of the southern coasts.
Height of snow-line on the Cordillera.
Descent of glaciers to the sea.
Icebergs formed.
Transportal of boulders.
Climate and productions of the Antarctic Islands.
Preservation of frozen carcasses.
Recapitulation.

STRAIT OF MAGELLAN.–CLIMATE OF THE SOUTHERN COASTS.

In the end of May 1834 we entered for a second time the eastern
mouth of the Strait of Magellan. The country on both sides of this
part of the Strait consists of nearly level plains, like those of
Patagonia. Cape Negro, a little within the second Narrows, may be
considered as the point where the land begins to assume the marked
features of Tierra del Fuego. On the east coast, south of the
Strait, broken park-like scenery in a like manner connects these
two countries, which are opposed to each other in almost every
feature. It is truly surprising to find in a space of twenty miles
such a change in the landscape. If we take a rather greater
distance, as between Port Famine and Gregory Bay, that is about
sixty miles, the difference is still more wonderful. At the former
place we have rounded mountains concealed by impervious forests,
which are drenched with the rain brought by an endless succession
of gales; while at Cape Gregory there is a clear and bright blue
sky over the dry and sterile plains. The atmospheric currents,
although rapid, turbulent, and unconfined by any apparent limits,
yet seem to follow, like a river in its bed, a regularly determined
course. (11/1. The south-westerly breezes are generally very dry.
January 29th, being at anchor under Cape Gregory: a very hard gale
from west by south, clear sky with few cumuli; temperature 57
degrees, dew-point 36 degrees,–difference 21 degrees. On January
15th, at Port St. Julian: in the morning light winds with much
rain, followed by a very heavy squall with rain,–settled into
heavy gale with large cumuli,–cleared up, blowing very strong from
south-south-west. Temperature 60 degrees, dew-point 42
degrees,–difference 18 degrees.)

During our previous visit (in January), we had an interview at Cape
Gregory with the famous so-called gigantic Patagonians, who gave us
a cordial reception. Their height appears greater than it really
is, from their large guanaco mantles, their long flowing hair, and
general figure: on an average their height is about six feet, with
some men taller and only a few shorter; and the women are also
tall; altogether they are certainly the tallest race which we
anywhere saw. In features they strikingly resemble the more
northern Indians whom I saw with Rosas, but they have a wilder and
more formidable appearance: their faces were much painted with red
and black, and one man was ringed and dotted with white like a
Fuegian. Captain Fitz Roy offered to take any three of them on
board, and all seemed determined to be of the three. It was long
before we could clear the boat; at last we got on board with our
three giants, who dined with the Captain, and behaved quite like
gentlemen, helping themselves with knives, forks, and spoons:
nothing was so much relished as sugar. This tribe has had so much
communication with sealers and whalers, that most of the men can
speak a little English and Spanish; and they are half civilised,
and proportionally demoralised.

The next morning a large party went on shore, to barter for skins
and ostrich-feathers; fire-arms being refused, tobacco was in
greatest request, far more so than axes or tools. The whole
population of the toldos, men, women, and children, were arranged
on a bank. It was an amusing scene, and it was impossible not to
like the so-called giants, they were so thoroughly good-humoured
and unsuspecting: they asked us to come again. They seem to like to
have Europeans to live with them; and old Maria, an important woman
in the tribe, once begged Mr. Low to leave any one of his sailors
with them. They spend the greater part of the year here; but in
summer they hunt along the foot of the Cordillera: sometimes they
travel as far as the Rio Negro, 750 miles to the north. They are
well stocked with horses, each man having, according to Mr. Low,
six or seven, and all the women, and even children, their one own
horse. In the time of Sarmiento (1580) these Indians had bows and
arrows, now long since disused; they then also possessed some
horses. This is a very curious fact, showing the extraordinarily
rapid multiplication of horses in South America. The horse was
first landed at Buenos Ayres in 1537, and the colony being then for
a time deserted, the horse ran wild (11/2. Rengger “Natur. der
Saugethiere von Paraguay” S. 334.); in 1580, only forty-three years
afterwards, we hear of them at the Strait of Magellan! Mr. Low
informs me, that a neighbouring tribe of foot-Indians is now
changing into horse-Indians: the tribe at Gregory Bay giving them
their worn-out horses, and sending in winter a few of their best
skilled men to hunt for them.

JUNE 1, 1834.

(PLATE 52. PORT FAMINE, MAGELLAN.)

We anchored in the fine bay of Port Famine. It was now the
beginning of winter, and I never saw a more cheerless prospect; the
dusky woods, piebald with snow, could be only seen indistinctly
through a drizzling hazy atmosphere. We were, however, lucky in
getting two fine days. On one of these, Mount Sarmiento, a distant
mountain 6800 feet high, presented a very noble spectacle. I was
frequently surprised, in the scenery of Tierra del Fuego, at the
little apparent elevation of mountains really lofty. I suspect it
is owing to a cause which would not at first be imagined, namely,
that the whole mass, from the summit to the water’s edge, is
generally in full view. I remember having seen a mountain, first
from the Beagle Channel, where the whole sweep from the summit to
the base was full in view, and then from Ponsonby Sound across
several successive ridges; and it was curious to observe in the
latter case, as each fresh ridge afforded fresh means of judging of
the distance, how the mountain rose in height.

Before reaching Port Famine, two men were seen running along the
shore and hailing the ship. A boat was sent for them. They turned
out to be two sailors who had run away from a sealing-vessel, and
had joined the Patagonians. These Indians had treated them with
their usual disinterested hospitality. They had parted company
through accident, and were then proceeding to Port Famine in hopes
of finding some ship. I daresay they were worthless vagabonds, but
I never saw more miserable-looking ones. They had been living for
some days on mussel-shells and berries, and their tattered clothes
had been burnt by sleeping so near their fires. They had been
exposed night and day, without any shelter, to the late incessant
gales, with rain, sleet, and snow, and yet they were in good
health.

(PLATE 53. PATAGONIAN BOLAS.)

(PLATE 54. PATAGONIAN SPURS AND PIPE.)

During our stay at Port Famine, the Fuegians twice came and plagued
us. As there were many instruments, clothes, and men on shore, it
was thought necessary to frighten them away. The first time a few
great guns were fired, when they were far distant. It was most
ludicrous to watch through a glass the Indians, as often as the
shot struck the water, take up stones, and, as a bold defiance,
throw them towards the ship, though about a mile and a half
distant! A boat was then sent with orders to fire a few
musket-shots wide of them. The Fuegians hid themselves behind the
trees, and for every discharge of the muskets they fired their
arrows; all, however, fell short of the boat, and the officer as he
pointed at them laughed. This made the Fuegians frantic with
passion, and they shook their mantles in vain rage. At last, seeing
the balls cut and strike the trees, they ran away, and we were left
in peace and quietness. During the former voyage the Fuegians were
here very troublesome, and to frighten them a rocket was fired at
night over their wigwams; it answered effectually, and one of the
officers told me that the clamour first raised, and the barking of
the dogs, was quite ludicrous in contrast with the profound silence
which in a minute or two afterwards prevailed. The next morning not
a single Fuegian was in the neighbourhood.

When the “Beagle” was here in the month of February, I started one
morning at four o’clock to ascend Mount Tarn, which is 2600 feet
high, and is the most elevated point in this immediate district. We
went in a boat to the foot of the mountain (but unluckily not to
the best part), and then began our ascent. The forest commences at
the line of high-water mark, and during the first two hours I gave
over all hopes of reaching the summit. So thick was the wood, that
it was necessary to have constant recourse to the compass; for
every landmark, though in a mountainous country, was completely
shut out. In the deep ravines the death-like scene of desolation
exceeded all description; outside it was blowing a gale, but in
these hollows not even a breath of wind stirred the leaves of the
tallest trees. So gloomy, cold, and wet was every part, that not
even the fungi, mosses, or ferns could flourish. In the valleys it
was scarcely possible to crawl along, they were so completely
barricaded by great mouldering trunks, which had fallen down in
every direction. When passing over these natural bridges, one’s
course was often arrested by sinking knee deep into the rotten
wood; at other times, when attempting to lean against a firm tree,
one was startled by finding a mass of decayed matter ready to fall
at the slightest touch. We at last found ourselves among the
stunted trees, and then soon reached the bare ridge, which
conducted us to the summit. Here was a view characteristic of
Tierra del Fuego; irregular chains of hills, mottled with patches
of snow, deep yellowish-green valleys, and arms of the sea
intersecting the land in many directions. The strong wind was
piercingly cold, and the atmosphere rather hazy, so that we did not
stay long on the top of the mountain. Our descent was not quite so
laborious as our ascent, for the weight of the body forced a
passage, and all the slips and falls were in the right direction.

I have already mentioned the sombre and dull character of the
evergreen forests, in which two or three species of trees grow, to
the exclusion of all others. (11/3. Captain Fitz Roy informs me
that in April (our October) the leaves of those trees which grow
near the base of the mountains change colour, but not those on the
more elevated parts. I remember having read some observations,
showing that in England the leaves fall earlier in a warm and fine
autumn than in a late and cold one. The change in the colour being
here retarded in the more elevated, and therefore colder
situations, must be owing to the same general law of vegetation.
The trees of Tierra del Fuego during no part of the year entirely
shed their leaves.) Above the forest land there are many dwarf
alpine plants, which all spring from the mass of peat, and help to
compose it: these plants are very remarkable from their close
alliance with the species growing on the mountains of Europe,
though so many thousand miles distant. The central part of Tierra
del Fuego, where the clay-slate formation occurs, is most
favourable to the growth of trees; on the outer coast the poorer
granitic soil, and a situation more exposed to the violent winds,
do not allow of their attaining any great size. Near Port Famine I
have seen more large trees than anywhere else: I measured a
Winter’s Bark which was four feet six inches in girth, and several
of the beech were as much as thirteen feet. Captain King also
mentions a beech which was seven feet in diameter seventeen feet
above the roots.

(PLATE 55. CYTTARIA DARWINII.)

There is one vegetable production deserving notice from its
importance as an article of food to the Fuegians. It is a globular,
bright-yellow fungus, which grows in vast numbers on the
beech-trees. When young it is elastic and turgid, with a smooth
surface; but when mature, it shrinks, becomes tougher, and has its
entire surface deeply pitted or honeycombed, as represented in
Plate 55. This fungus belongs to a new and curious genus (11/4.
Described from my specimens and notes by the Reverend J.M. Berkeley
in the “Linnean Transactions” volume 19 page 37, under the name of
Cyttaria Darwinii: the Chilean species is the C. Berteroii. This
genus is allied to Bulgaria.); I found a second species on another
species of beech in Chile: and Dr. Hooker informs me that just
lately a third species has been discovered on a third species of
beech in Van Dieman’s Land. How singular is this relationship
between parasitical fungi and the trees on which they grow, in
distant parts of the world! In Tierra del Fuego the fungus in its
tough and mature state is collected in large quantities by the
women and children, and is eaten un-cooked. It has a mucilaginous,
slightly sweet taste, with a faint smell like that of a mushroom.
With the exception of a few berries, chiefly of a dwarf arbutus,
the natives eat no vegetable food besides this fungus. In New
Zealand, before the introduction of the potato, the roots of the
fern were largely consumed; at the present time, I believe, Tierra
del Fuego is the only country in the world where a cryptogamic
plant affords a staple article of food.

The zoology of Tierra del Fuego, as might have been expected from
the nature of its climate and vegetation, is very poor. Of
mammalia, besides whales and seals, there is one bat, a kind of
mouse (Reithrodon chinchilloides), two true mice, a ctenomys allied
to or identical with the tucutuco, two foxes (Canis Magellanicus
and C. Azarae), a sea-otter, the guanaco, and a deer. Most of these
animals inhabit only the drier eastern parts of the country; and
the deer has never been seen south of the Strait of Magellan.
Observing the general correspondence of the cliffs of soft
sandstone, mud, and shingle, on the opposite sides of the Strait,
and on some intervening islands, one is strongly tempted to believe
that the land was once joined, and thus allowed animals so delicate
and helpless as the tucutuco and Reithrodon to pass over. The
correspondence of the cliffs is far from proving any junction;
because such cliffs generally are formed by the intersection of
sloping deposits, which, before the elevation of the land, had been
accumulated near the then existing shores. It is, however, a
remarkable coincidence, that in the two large islands cut off by
the Beagle Channel from the rest of Tierra del Fuego, one has
cliffs composed of matter that may be called stratified alluvium,
which front similar ones on the opposite side of the
channel,–while the other is exclusively bordered by old
crystalline rocks; in the former, called Navarin Island, both foxes
and guanacos occur; but in the latter, Hoste Island, although
similar in every respect, and only separated by a channel a little
more than half a mile wide, I have the word of Jemmy Button for
saying that neither of these animals is found.

The gloomy woods are inhabited by few birds: occasionally the
plaintive note of a white-tufted tyrant-flycatcher (Myiobius
albiceps) may be heard, concealed near the summit of the most lofty
trees; and more rarely the loud strange cry of a black woodpecker,
with a fine scarlet crest on its head. A little, dusky-coloured
wren (Scytalopus Magellanicus) hops in a skulking manner among the
entangled mass of the fallen and decaying trunks. But the creeper
(Oxyurus tupinieri) is the commonest bird in the country.
Throughout the beech forests, high up and low down, in the most
gloomy, wet, and impenetrable ravines, it may be met with. This
little bird no doubt appears more numerous than it really is, from
its habit of following with seeming curiosity any person who enters
these silent woods: continually uttering a harsh twitter, it
flutters from tree to tree, within a few feet of the intruder’s
face. It is far from wishing for the modest concealment of the true
creeper (Certhia familiaris); nor does it, like that bird, run up
the trunks of trees, but industriously, after the manner of a
willow-wren, hops about, and searches for insects on every twig and
branch. In the more open parts, three or four species of finches, a
thrush, a starling (or Icterus), two Opetiorhynchi, and several
hawks and owls occur.

The absence of any species whatever in the whole class of Reptiles
is a marked feature in the zoology of this country, as well as in
that of the Falkland Islands. I do not ground this statement merely
on my own observation, but I heard it from the Spanish inhabitants
of the latter place, and from Jemmy Button with regard to Tierra
del Fuego. On the banks of the Santa Cruz, in 50 degrees south, I
saw a frog; and it is not improbable that these animals, as well as
lizards, may be found as far south as the Strait of Magellan, where
the country retains the character of Patagonia; but within the damp
and cold limit of Tierra del Fuego not one occurs. That the climate
would not have suited some of the orders, such as lizards, might
have been foreseen; but with respect to frogs, this was not so
obvious.

Beetles occur in very small numbers: it was long before I could
believe that a country as large as Scotland, covered with vegetable
productions and with a variety of stations, could be so
unproductive. The few which I found were alpine species (Harpalidae
and Heteromidae) living under stones. The vegetable-feeding
Chrysomelidae, so eminently characteristic of the Tropics, are here
almost entirely absent (11/5. I believe I must except one alpine
Haltica, and a single specimen of a Melasoma. Mr. Waterhouse
informs me, that of the Harpalidae there are eight or nine
species–the forms of the greater number being very peculiar; of
Heteromera, four or five species; of Rhyncophora, six or seven; and
of the following families one species in each: Staphylinidae,
Elateridae, Cebrionidae, Melolonthidae. The species in the other
orders are even fewer. In all the orders, the scarcity of the
individuals is even more remarkable than that of the species. Most
of the Coleoptera have been carefully described by Mr. Waterhouse
in the “Annals of Natural History.”); I saw very few flies,
butterflies, or bees, and no crickets or Orthoptera. In the pools
of water I found but few aquatic beetles, and not any fresh-water
shells: Succinea at first appears an exception; but here it must be
called a terrestrial shell, for it lives on the damp herbage far
from water. Land-shells could be procured only in the same alpine
situations with the beetles. I have already contrasted the climate
as well as the general appearance of Tierra del Fuego with that of
Patagonia; and the difference is strongly exemplified in the
entomology. I do not believe they have one species in common;
certainly the general character of the insects is widely different.

If we turn from the land to the sea, we shall find the latter as
abundantly stocked with living creatures as the former is poorly
so. In all parts of the world a rocky and partially protected shore
perhaps supports, in a given space, a greater number of individual
animals than any other station. There is one marine production
which, from its importance, is worthy of a particular history. It
is the kelp, or Macrocystis pyrifera. This plant grows on every
rock from low-water mark to a great depth, both on the outer coast
and within the channels. (11/6. Its geographical range is
remarkably wide; it is found from the extreme southern islets near
Cape Horn, as far north on the eastern coast (according to
information given me by Mr. Stokes) as latitude 43 degrees,–but on
the western coast, as Dr. Hooker tells me, it extends to the R. San
Francisco in California, and perhaps even to Kamtschatka. We thus
have an immense range in latitude; and as Cook, who must have been
well acquainted with the species, found it at Kerguelen Land, no
less than 140 degrees in longitude.) I believe, during the voyages
of the “Adventure” and “Beagle,” not one rock near the surface was
discovered which was not buoyed by this floating weed. The good
service it thus affords to vessels navigating near this stormy land
is evident; and it certainly has saved many a one from being
wrecked. I know few things more surprising than to see this plant
growing and flourishing amidst those great breakers of the western
ocean, which no mass of rock, let it be ever so hard, can long
resist. The stem is round, slimy, and smooth, and seldom has a
diameter of so much as an inch. A few taken together are
sufficiently strong to support the weight of the large loose
stones, to which in the inland channels they grow attached; and yet
some of these stones were so heavy that when drawn to the surface,
they could scarcely be lifted into a boat by one person. Captain
Cook, in his second voyage, says that this plant at Kerguelen Land
rises from a greater depth than twenty-four fathoms; “and as it
does not grow in a perpendicular direction, but makes a very acute
angle with the bottom, and much of it afterwards spreads many
fathoms on the surface of the sea, I am well warranted to say that
some of it grows to the length of sixty fathoms and upwards.” I do
not suppose the stem of any other plant attains so great a length
as three hundred and sixty feet, as stated by Captain Cook. Captain
Fitz Roy, moreover, found it growing up from the greater depth of
forty-five fathoms. (11/7. “Voyages of the ‘Adventure’ and
‘Beagle'” volume 1 page 363. It appears that seaweed grows
extremely quick. Mr. Stephenson found Wilson’s “Voyage round
Scotland” volume 2 page 228, that a rock uncovered only at
spring-tides, which had been chiselled smooth in November, on the
following May, that is, within six months afterwards, was thickly
covered with Fucus digitatus two feet, and F. esculentus six feet,
in length.) The beds of this sea-weed, even when of not great
breadth, make excellent natural floating breakwaters. It is quite
curious to see, in an exposed harbour, how soon the waves from the
open sea, as they travel through the straggling stems, sink in
height, and pass into smooth water.

The number of living creatures of all Orders, whose existence
intimately depends on the kelp, is wonderful. A great volume might
be written, describing the inhabitants of one of these beds of
seaweed. Almost all the leaves, excepting those that float on the
surface, are so thickly incrusted with corallines as to be of a
white colour. We find exquisitely delicate structures, some
inhabited by simple hydra-like polypi, others by more organised
kinds, and beautiful compound Ascidiae. On the leaves, also,
various patelliform shells, Trochi, uncovered molluscs, and some
bivalves are attached. Innumerable crustacea frequent every part of
the plant. On shaking the great entangled roots, a pile of small
fish, shells, cuttlefish, crabs of all orders, sea-eggs, starfish,
beautiful Holothuriae, Planariae, and crawling nereidous animals of
a multitude of forms, all fall out together. Often as I recurred to
a branch of the kelp, I never failed to discover animals of new and
curious structures. In Chiloe, where the kelp does not thrive very
well, the numerous shells, corallines, and crustacea are absent;
but there yet remain a few of the Flustraceae, and some compound
Ascidiae; the latter, however, are of different species from those
in Tierra del Fuego; we see here the fucus possessing a wider range
than the animals which use it as an abode. I can only compare these
great aquatic forests of the southern hemisphere with the
terrestrial ones in the intertropical regions. Yet if in any
country a forest was destroyed, I do not believe nearly so many
species of animals would perish as would here, from the destruction
of the kelp. Amidst the leaves of this plant numerous species of
fish live, which nowhere else could find food or shelter; with
their destruction the many cormorants and other fishing birds, the
otters, seals, and porpoises, would soon perish also; and lastly,
the Fuegian savage, the miserable lord of this miserable land,
would redouble his cannibal feast, decrease in numbers, and perhaps
cease to exist.

JUNE 8, 1834.

We weighed anchor early in the morning and left Port Famine.
Captain Fitz Roy determined to leave the Strait of Magellan by the
Magdalen Channel, which had not long been discovered. Our course
lay due south, down that gloomy passage which I have before alluded
to as appearing to lead to another and worse world. The wind was
fair, but the atmosphere was very thick; so that we missed much
curious scenery. The dark ragged clouds were rapidly driven over
the mountains, from their summits nearly down to their bases. The
glimpses which we caught through the dusky mass were highly
interesting; jagged points, cones of snow, blue glaciers, strong
outlines, marked on a lurid sky, were seen at different distances
and heights. In the midst of such scenery we anchored at Cape Turn,
close to Mount Sarmiento, which was then hidden in the clouds. At
the base of the lofty and almost perpendicular sides of our little
cove there was one deserted wigwam, and it alone reminded us that
man sometimes wandered into these desolate regions. But it would be
difficult to imagine a scene where he seemed to have fewer claims
or less authority. The inanimate works of nature–rock, ice, snow,
wind, and water, all warring with each other, yet combined against
man–here reigned in absolute sovereignty.

JUNE 9, 1834.

In the morning we were delighted by seeing the veil of mist
gradually rise from Sarmiento, and display it to our view. This
mountain, which is one of the highest in Tierra del Fuego, has an
altitude of 6800 feet. Its base, for about an eighth of its total
height, is clothed by dusky woods, and above this a field of snow
extends to the summit. These vast piles of snow, which never melt,
and seem destined to last as long as the world holds together,
present a noble and even sublime spectacle. The outline of the
mountain was admirably clear and defined. Owing to the abundance of
light reflected from the white and glittering surface, no shadows
were cast on any part; and those lines which intersected the sky
could alone be distinguished: hence the mass stood out in the
boldest relief. Several glaciers descended in a winding course from
the upper great expanse of snow to the sea-coast: they may be
likened to great frozen Niagaras; and perhaps these cataracts of
blue ice are full as beautiful as the moving ones of water. By
night we reached the western part of the channel; but the water was
so deep that no anchorage could be found. We were in consequence
obliged to stand off and on in this narrow arm of the sea, during a
pitch-dark night of fourteen hours long.

JUNE 10, 1834.

In the morning we made the best of our way into the open Pacific.
The western coast generally consists of low, rounded, quite barren
hills of granite and greenstone. Sir J. Narborough called one part
South Desolation, because it is “so desolate a land to behold:” and
well indeed might he say so. Outside the main islands there are
numberless scattered rocks on which the long swell of the open
ocean incessantly rages. We passed out between the East and West
Furies; and a little farther northward there are so many breakers
that the sea is called the Milky Way. One sight of such a coast is
enough to make a landsman dream for a week about shipwrecks, peril,
and death; and with this sight we bade farewell for ever to Tierra
del Fuego.

The following discussion on the climate of the southern parts of
the continent with relation to its productions, on the snow-line,
on the extraordinarily low descent of the glaciers, and on the zone
of perpetual congelation in the antarctic islands, may be passed
over by any one not interested in these curious subjects, or the
final recapitulation alone may be read. I shall, however, here give
only an abstract, and must refer for details to the Thirteenth
Chapter and the Appendix of the former edition of this work.

ON THE CLIMATE AND PRODUCTIONS OF TIERRA DEL FUEGO AND OF THE
SOUTH-WEST COAST.

The following table gives the mean temperature of Tierra del
Fuego, the Falkland Islands, and, for comparison, that of
Dublin:–

Latitude    Summer Winter Mean of Summer
degrees ‘ Temp.    Temp.     and Winter
deg. F. deg. F.     deg. F.
—————————————————————
Tierra del Fuego 53 38 S.    50     33.08         41.54
Falkland Islands 51 38 S.    51        —            —
Dublin            53 21 N.    59.54    39.2         49.37

Hence we see that the central part of Tierra del Fuego is colder in
winter, and no less than 9 1/2 degrees less hot in summer, than
Dublin. According to von Buch the mean temperature of July (not the
hottest month in the year) at Saltenfiord in Norway, is as high as
57.8 degrees, and this place is actually 13 degrees nearer the pole
than Port Famine! (11/8. With respect to Tierra del Fuego, the
results are deduced from the observations of Captain King
“Geographical Journal” 1830, and those taken on board the “Beagle.”
For the Falkland Islands, I am indebted to Captain Sulivan for the
mean of the mean temperature (reduced from careful observation at
midnight, 8 A.M., noon, and 8 P.M.) of the three hottest months,
namely, December, January, and February. The temperature of Dublin
is taken from Barton.) Inhospitable as this climate appears to our
feelings, evergreen trees flourish luxuriantly under it.
Humming-birds may be seen sucking the flowers, and parrots feeding
on the seeds of the Winter’s Bark, in latitude 55 degrees south. I
have already remarked to what a degree the sea swarms with living
creatures; and the shells (such as the Patellae, Fissurellae,
Chitons, and Barnacles), according to Mr. G.B. Sowerby, are of a
much larger size, and of a more vigorous growth, than the analogous
species in the northern hemisphere. A large Voluta is abundant in
southern Tierra del Fuego and the Falkland Islands. At Bahia
Blanca, in latitude 39 degrees south, the most abundant shells were
three species of Oliva (one of large size), one or two Volutas, and
a Terebra. Now these are amongst the best characterised tropical
forms. It is doubtful whether even one small species of Oliva
exists on the southern shores of Europe, and there are no species
of the two other genera. If a geologist were to find in latitude 39
degrees on the coast of Portugal a bed containing numerous shells
belonging to three species of Oliva, to a Voluta, and Terebra, he
would probably assert that the climate at the period of their
existence must have been tropical; but, judging from South America,
such an inference might be erroneous.

The equable, humid, and windy climate of Tierra del Fuego extends,
with only a small increase of heat, for many degrees along the west
coast of the continent. The forests for 600 miles northward of Cape
Horn, have a very similar aspect. As a proof of the equable
climate, even for 300 or 400 miles still farther northward, I may
mention that in Chiloe (corresponding in latitude with the northern
parts of Spain) the peach seldom produces fruit, whilst
strawberries and apples thrive to perfection. Even the crops of
barley and wheat are often brought into the houses to be dried and
ripened. (11/9. Agüeros “Descrip. Hist. de la Prov. de Chiloé” 1791
page 94.) At Valdivia (in the same latitude of 40 degrees with
Madrid) grapes and figs ripen, but are not common; olives seldom
ripen even partially, and oranges not at all. These fruits, in
corresponding latitudes in Europe, are well known to succeed to
perfection; and even in this continent, at the Rio Negro, under
nearly the same parallel with Valdivia, sweet potatoes
(convolvulus) are cultivated; and grapes, figs, olives, oranges,
water and musk melons, produce abundant fruit.

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Although the humid
and equable climate of Chiloe, and of the coast northward and
southward of it, is so unfavourable to our fruits, yet the native
forests, from latitude 45 to 38 degrees, almost rival in luxuriance
those of the glowing intertropical regions. Stately trees of many
kinds, with smooth and highly coloured barks, are loaded by
parasitical monocotyledonous plants; large and elegant ferns are
numerous, and arborescent grasses entwine the trees into one
entangled mass to the height of thirty or forty feet above the
ground. Palm-trees grow in latitude 37 degrees; an arborescent
grass, very like a bamboo, in 40 degrees; and another closely
allied kind, of great length, but not erect, flourishes even as far
south as 45 degrees south.

ON THE HEIGHT OF THE SNOW-LINE, AND ON THE DESCENT OF THE GLACIERS,
IN SOUTH AMERICA.

For the detailed authorities for the following table, I must
refer to the former edition:–

Height in feet
Latitude                 of Snow-line         Observer
—————————————————————-
Equatorial region;
mean result             15,748                Humboldt.

Bolivia, latitude
16 to 18 degrees south 17,000                Pentland.

Central Chile, latitude
33 degrees south         14,500 to 15,000     Gillies and the
Author.

Chiloe, latitude
41 to 43 degrees south 6,000                 Officers of the
“Beagle” and the
Author.

Tierra del Fuego
54 degrees south         3,500 – 4,000 King.
An equable climate, evidently due to the large area of sea compared
with the land, seems to extend over the greater part of the
southern hemisphere; and as a consequence, the vegetation partakes
of a semi-tropical character. Tree-ferns thrive luxuriantly in Van
Diemen’s Land (latitude 45 degrees), and I measured one trunk no
less than six feet in circumference. An arborescent fern was found
by Forster in New Zealand in 46 degrees, where orchideous plants
are parasitical on the trees. In the Auckland Islands, ferns,
according to Dr. Dieffenbach have trunks so thick and high that
they may be almost called tree-ferns; and in these islands, and
even as far south as latitude 55 degrees in the Macquarie Islands,
parrots abound. (11/10. See the German Translation of this Journal;
and for the other facts Mr. Brown’s Appendix to Flinders’s
“Voyage.”)

As the height of the plane of perpetual snow seems chiefly to be
determined by the extreme heat of the summer, rather than by the
mean temperature of the year, we ought not to be surprised at its
descent in the Strait of Magellan, where the summer is so cool, to
only 3500 or 4000 feet above the level of the sea; although in
Norway, we must travel to between latitude 67 and 70 degrees north,
that is, about 14 degrees nearer the pole, to meet with perpetual
snow at this low level. The difference in height, namely, about
9000 feet, between the snow-line on the Cordillera behind Chiloe
(with its highest points ranging from only 5600 to 7500 feet) and
in central Chile (a distance of only 9 degrees of latitude), is
truly wonderful. (11/11. On the Cordillera of central Chile, I
believe the snow-line varies exceedingly in height in different
summers. I was assured that during one very dry and long summer,
all the snow disappeared from Aconcagua, although it attains the
prodigious height of 23,000 feet. It is probable that much of the
snow at these great heights is evaporated, rather than thawed.) The
land from the southward of Chiloe to near Concepcion (latitude 37
degrees) is hidden by one dense forest dripping with moisture. The
sky is cloudy, and we have seen how badly the fruits of southern
Europe succeed. In central Chile, on the other hand, a little
northward of Concepcion, the sky is generally clear, rain does not
fall for the seven summer months, and southern European fruits
succeed admirably; and even the sugar-cane has been cultivated.
(11/12. Miers’s “Chile” volume 1 page 415. It is said that the
sugar-cane grew at Ingenio, latitude 32 to 33 degrees, but not in
sufficient quantity to make the manufacture profitable. In the
valley of Quillota, south of Ingenio, I saw some large date-palm
trees.) No doubt the plane of perpetual snow undergoes the above
remarkable flexure of 9000 feet, unparalleled in other parts of the
world, not far from the latitude of Concepcion, where the land
ceases to be covered with forest-trees; for trees in South America
indicate a rainy climate, and rain a clouded sky and little heat in
summer.

(PLATE 56. EYRE SOUND.)

The descent of glaciers to the sea must, I conceive, mainly depend
(subject, of course, to a proper supply of snow in the upper
region) on the lowness of the line of perpetual snow on steep
mountains near the coast. As the snow-line is so low in Tierra del
Fuego, we might have expected that many of the glaciers would have
reached the sea. Nevertheless I was astonished when I first saw a
range, only from 3000 to 4000 feet in height, in the latitude of
Cumberland, with every valley filled with streams of ice descending
to the sea-coast. Almost every arm of the sea, which penetrates to
the interior higher chain, not only in Tierra del Fuego, but on the
coast for 650 miles northwards, is terminated by “tremendous and
astonishing glaciers,” as described by one of the officers on the
survey. Great masses of ice frequently fall from these icy cliffs,
and the crash reverberates like the broadside of a man-of-war
through the lonely channels. These falls, as noticed in the last
chapter, produce great waves which break on the adjoining coasts.
It is known that earthquakes frequently cause masses of earth to
fall from sea-cliffs: how terrific, then, would be the effect of a
severe shock (and such occur here (11/13. Bulkeley’s and Cummin’s
“Faithful Narrative of the Loss of the Wager.” The earthquake
happened August 25, 1741.)) on a body like a glacier, already in
motion, and traversed by fissures! I can readily believe that the
water would be fairly beaten back out of the deepest channel, and
then, returning with an overwhelming force, would whirl about huge
masses of rock like so much chaff. In Eyre’s Sound, in the latitude
of Paris, there are immense glaciers, and yet the loftiest
neighbouring mountain is only 6200 feet high. In this Sound, about
fifty icebergs were seen at one time floating outwards, and one of
them must have been AT LEAST 168 feet in total height. Some of the
icebergs were loaded with blocks of no inconsiderable size, of
granite and other rocks, different from the clay-slate of the
surrounding mountains.

(PLATE 57. GLACIER IN GULF OF PENAS.)

The glacier farthest from the Pole, surveyed during the voyages of
the “Adventure” and “Beagle,” is in latitude 46 degrees 50′, in the
Gulf of Penas. It is 15 miles long, and in one part 7 broad, and
descends to the sea-coast. But even a few miles northward of this
glacier, in the Laguna de San Rafael, some Spanish missionaries
encountered “many icebergs, some great, some small, and others
middle-sized,” in a narrow arm of the sea, on the 22 of the month
corresponding with our June, and in a latitude corresponding with
that of the Lake of Geneva! (11/14. Agüeros “Desc. Hist. de Chiloé”
page 227.)

In Europe, the most southern glacier which comes down to the sea is
met with, according to Von Buch, on the coast of Norway, in
latitude 67 degrees. Now, this is more than 20 degrees of latitude,
or 1230 miles, nearer the pole than the Laguna de San Rafael. The
position of the glaciers at this place and in the Gulf of Penas may
be put even in a more striking point of view, for they descend to
the sea-coast within 7 1/2 degrees of latitude, or 450 miles, of a
harbour, where three species of Oliva, a Voluta, and a Terebra, are
the commonest shells, within less than 9 degrees from where palms
grow, within 4 1/2 degrees of a region where the jaguar and puma
range over the plains, less than 2 1/2 degrees from arborescent
grasses, and (looking to the westward in the same hemisphere) less
than 2 degrees from orchideous parasites, and within a single
degree of tree-ferns!

These facts are of high geological interest with respect to the
climate of the northern hemisphere, at the period when boulders
were transported. I will not here detail how simply the theory of
icebergs being charged with fragments of rock explains the origin
and position of the gigantic boulders of eastern Tierra del Fuego,
on the high plain of Santa Cruz, and on the island of Chiloe. In
Tierra del Fuego the greater number of boulders lie on the lines of
old sea-channels, now converted into dry valleys by the elevation
of the land. They are associated with a great unstratified
formation of mud and sand, containing rounded and angular fragments
of all sizes, which has originated in the repeated ploughing up of
the sea-bottom by the stranding of icebergs, and by the matter
transported on them. (11/15. “Geological Transactions” volume 6
page 415.) Few geologists now doubt that those erratic boulders
which lie near lofty mountains have been pushed forward by the
glaciers themselves, and that those distant from mountains, and
embedded in subaqueous deposits, have been conveyed thither either
on icebergs, or frozen in coast-ice. The connection between the
transportal of boulders and the presence of ice in some form, is
strikingly shown by their geographical distribution over the earth.
In South America they are not found farther than 48 degrees of
latitude, measured from the southern pole; in North America it
appears that the limit of their transportal extends to 53 1/2
degrees from the northern pole; but in Europe to not more than 40
degrees of latitude, measured from the same point. On the other
hand, in the intertropical parts of America, Asia, and Africa, they
have never been observed; nor at the Cape of Good Hope, nor in
Australia. (11/16. I have given details (the first, I believe,
published) on this subject in the first edition, and in the
Appendix to it. I have there shown that the apparent exceptions to
the absence of erratic boulders in certain hot countries are due to
erroneous observations; several statements there given I have since
found confirmed by various authors.)

ON THE CLIMATE AND PRODUCTIONS OF THE ANTARCTIC ISLANDS.

Considering the rankness of the vegetation in Tierra del Fuego, and
on the coast northward of it, the condition of the islands south
and south-west of America is truly surprising. Sandwich Land, in
the latitude of the north part of Scotland, was found by Cook,
during the hottest month of the year, “covered many fathoms thick
with everlasting snow;” and there seems to be scarcely any
vegetation. Georgia, an island 96 miles long and 10 broad, in the
latitude of Yorkshire, “in the very height of summer, is in a
manner wholly covered with frozen snow.” It can boast only of moss,
some tufts of grass, and wild burnet; it has only one land-bird
(Anthus correndera), yet Iceland, which is 10 degrees nearer the
pole, has, according to Mackenzie, fifteen land-birds. The South
Shetland Islands, in the same latitude as the southern half of
Norway, possess only some lichens, moss, and a little grass; and
Lieutenant Kendall found the bay in which he was at anchor,
beginning to freeze at a period corresponding with our 8th of
September. (11/17. “Geographical Journal” 1830 pages 65, 66.) The
soil here consists of ice and volcanic ashes interstratified; and
at a little depth beneath the surface it must remain perpetually
congealed, for Lieutenant Kendall found the body of a foreign
sailor which had long been buried, with the flesh and all the
features perfectly preserved. It is a singular fact that on the two
great continents in the northern hemisphere (but not in the broken
land of Europe between them) we have the zone of perpetually frozen
under-soil in a low latitude–namely, in 56 degrees in North
America at the depth of three feet (11/18. Richardson’s “Append. to
Back’s Exped.” and Humboldt’s “Fragm. Asiat.” tome 2 page 386.),
and in 62 degrees in Siberia at the depth of twelve to fifteen
feet–as the result of a directly opposite condition of things to
those of the southern hemisphere. On the northern continents, the
winter is rendered excessively cold by the radiation from a large
area of land into a clear sky, nor is it moderated by the
warmth-bringing currents of the sea; the short summer, on the other
hand, is hot. In the Southern Ocean the winter is not so
excessively cold, but the summer is far less hot, for the clouded
sky seldom allows the sun to warm the ocean, itself a bad absorbent
of heat: and hence the mean temperature of the year, which
regulates the zone of perpetually congealed under-soil, is low. It
is evident that a rank vegetation, which does not so much require
heat as it does protection from intense cold, would approach much
nearer to this zone of perpetual congelation under the equable
climate of the southern hemisphere, than under the extreme climate
of the northern continents.

The case of the sailor’s body perfectly preserved in the icy soil
of the South Shetland Islands (latitude 62 to 63 degrees south), in
a rather lower latitude than that (latitude 64 degrees north) under
which Pallas found the frozen rhinoceros in Siberia, is very
interesting. Although it is a fallacy, as I have endeavoured to
show in a former chapter, to suppose that the larger quadrupeds
require a luxuriant vegetation for their support, nevertheless it
is important to find in the South Shetland Islands a frozen
under-soil within 360 miles of the forest-clad islands near Cape
Horn, where, as far as the BULK of vegetation is concerned, any
number of great quadrupeds might be supported. The perfect
preservation of the carcasses of the Siberian elephants and
rhinoceroses is certainly one of the most wonderful facts in
geology; but independently of the imagined difficulty of supplying
them with food from the adjoining countries, the whole case is not,
I think, so perplexing as it has generally been considered. The
plains of Siberia, like those of the Pampas, appear to have been
formed under the sea, into which rivers brought down the bodies of
many animals; of the greater number of these only the skeletons
have been preserved, but of others the perfect carcass. Now it is
known that in the shallow sea on the Arctic coast of America the
bottom freezes (11/19. Messrs. Dease and Simpson, in “Geographical
Journal” volume 8 pages 218 and 220.), and does not thaw in spring
so soon as the surface of the land, moreover, at greater depths,
where the bottom of the sea does not freeze, the mud a few feet
beneath the top layer might remain even in summer below 32 degrees,
as is the case on the land with the soil at the depth of a few
feet. At still greater depths the temperature of the mud and water
would probably not be low enough to preserve the flesh; and hence,
carcasses drifted beyond the shallow parts near an arctic coast,
would have only their skeletons preserved: now in the extreme
northern parts of Siberia bones are infinitely numerous, so that
even islets are said to be almost composed of them (11/20. Cuvier
“Ossemens Fossiles” tome 1 page 151, from Billing’s “Voyage.”); and
those islets lie no less than ten degrees of latitude north of the
place where Pallas found the frozen rhinoceros. On the other hand,
a carcass washed by a flood into a shallow part of the Arctic Sea,
would be preserved for an indefinite period, if it were soon
afterwards covered with mud sufficiently thick to prevent the heat
of the summer water penetrating to it; and if, when the sea-bottom
was upraised into land, the covering was sufficiently thick to
prevent the heat of the summer air and sun thawing and corrupting
it.

(PLATE 58. FLORA OF MAGELLAN.)

(PLATE 59. MACROCYSTIS PYRIFERA, OR MAGELLAN KELP.)

RECAPITULATION.

I will recapitulate the principal facts with regard to the climate,
ice-action, and organic productions of the southern hemisphere,
transposing the places in imagination to Europe, with which we are
so much better acquainted. Then, near Lisbon, the commonest
sea-shells, namely, three species of Oliva, a Voluta, and a
Terebra, would have a tropical character. In the southern provinces
of France, magnificent forests, intwined by arborescent grasses and
with the trees loaded with parasitical plants, would hide the face
of the land. The puma and the jaguar would haunt the Pyrenees. In
the latitude of Mont Blanc, but on an island as far westward as
Central North America, tree-ferns and parasitical Orchideae would
thrive amidst the thick woods. Even as far north as central Denmark
humming-birds would be seen fluttering about delicate flowers, and
parrots feeding amidst the evergreen woods; and in the sea there we
should have a Voluta, and all the shells of large size and vigorous
growth. Nevertheless, on some islands only 360 miles northward of
our new Cape Horn in Denmark, a carcass buried in the soil (or if
washed into a shallow sea, and covered up with mud) would be
preserved perpetually frozen. If some bold navigator attempted to
penetrate northward of these islands, he would run a thousand
dangers amidst gigantic icebergs, on some of which he would see
great blocks of rock borne far away from their original site.
Another island of large size in the latitude of southern Scotland,
but twice as far to the west, would be “almost wholly covered with
everlasting snow,” and would have each bay terminated by
ice-cliffs, whence great masses would be yearly detached: this
island would boast only of a little moss, grass, and burnet, and a
titlark would be its only land inhabitant. From our new Cape Horn
in Denmark, a chain of mountains, scarcely half the height of the
Alps, would run in a straight line due southward; and on its
western flank every deep creek of the sea, or fiord, would end in
“bold and astonishing glaciers.” These lonely channels would
frequently reverberate with the falls of ice, and so often would
great waves rush along their coasts; numerous icebergs, some as
tall as cathedrals, and occasionally loaded with “no inconsiderable
blocks of rock,” would be stranded on the outlying islets; at
intervals violent earthquakes would shoot prodigious masses of ice
into the waters below. Lastly, some missionaries attempting to
penetrate a long arm of the sea, would behold the not lofty
surrounding mountains, sending down their many grand icy streams to
the sea-coast, and their progress in the boats would be checked by
the innumerable floating icebergs, some small and some great; and
this would have occurred on our twenty-second of June, and where
the Lake of Geneva is now spread out! (11/21. In the former edition
and Appendix, I have given some facts on the transportal of erratic
boulders and icebergs in the Antarctic Ocean. This subject has
lately been treated excellently by Mr. Hayes, in the “Boston
Journal” volume 4 page 426. The author does not appear aware of a
case published by me “Geographical Journal” volume 9 page 528, of a
gigantic boulder embedded in an iceberg in the Antarctic Ocean,
almost certainly one hundred miles distant from any land, and
perhaps much more distant. In the Appendix I have discussed at
length the probability (at that time hardly thought of) of
icebergs, when stranded, grooving and polishing rocks, like
glaciers. This is now a very commonly received opinion; and I
cannot still avoid the suspicion that it is applicable even to such
cases as that of the Jura. Dr. Richardson has assured me that the
icebergs off North America push before them pebbles and sand, and
leave the submarine rocky flats quite bare; it is hardly possible
to doubt that such ledges must be polished and scored in the
direction of the set of the prevailing currents. Since writing that
Appendix I have seen in North Wales “London Philosophical Magazine”
volume 21 page 180) the adjoining action of glaciers and floating
icebergs.

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