Richthofen, Ferdinand Freiherr von. "Ueber den Gebirgsbau an der Nordküste von Formosa" [On the geological composition of Formosa's north coast]. Zeitschrift der Deutschen
geologischen Gesellschaft 2 (1860): 532-545. Translated by Tina Schneider;
edited by Douglas Fix.
[P. 532] Formosa consists of one high mountain range that seems to rise up to
12,000 feet above sea level (1). On the east coast the mountains
fall precipitously into the sea; in some places, such as near
the village of Chockeday, they drop sharply from a height of
6,000 to 7,000
The descent continues so abruptly that all soundings along the
coast show no bottom, with the exception of the few places where
penetrates the mountains and a creek has accumulated a cone of
debris with a steep slope on the bottom of the sea. To the west,
slope declines and extends gradually; this is the inhabited and
cultivated region of the island. To the north, the range ends
in hill country,
from which only isolated peaks emerge. Until recently, there
has been hardly any information on the geological composition
of the island,
the surface of which covers 600-700 geographic square miles,
apart from the old report by De Mailla that the country shows
traces of former
volcanic activity, in spite of the lack of verified documentation on the existence of active volcanoes(2), [p. 533]
and the more recent reiterated fact that there is coal near Kelung.
When the Royal Prussian frigate Thetis approached the Tamsui
harbor on the northern coast, I had the opportunity of looking
at some rocks
on the island. The ship could not enter the harbor because it
drew too large a draft, and, therefore, our stay was limited
to one day.
Because the site of inspection was not unfavorable and since
every statement of fact about such an unknown land is worthwhile,
that even a mere outline of a report such as the following one
will be accepted with the reader's indulgence.
1. Surface formation.
The northern tip of Formosa carries the name Syauki Point;
it is connected to the northwest and northeast coasts, both of
bend back towards the land in a flat curve. The innermost
portion of the former contains Tamsui harbor, and the harbor of
situated in the innermost part of the northeast coast. Tamsui
sits on the broadened estuary of a great river, while Kelung harbor
an indentation on the coast.
If you approach the northwest coast from the sea, you see two high, isolated
mountain massifs, between which the Tamsui River discharges; to the
left and to the right of these peaks there is a seemingly level plateau,
400-500 feet high. The northern mountains reach a height of 2800 English
feet, according to the English marine charts of the island and the
separate chart of Tamsui harbor; the southern mountains rise to 1720
feet. The former peak seems to be the beginning of a mountain range
that extends further to the east, while the southern massif is smaller,
more isolated and more abruptly precipitated. The forms of both are
reminiscent of trachyte mountains. Not long before reaching Formosa,
we had been in Nagasaki on Kyushu, which is surrounded by trachyte
mountains. Everyone was surprised by the similarities in the mountain
formations near Tamsui and those at the Japanese harbor. [p. 534] Only
the arrangement of the group is completely different on Formosa, especially
because of the isolated appearance of both mountain massifs. The northern mountain range falls towards the
coast with a slope rich in ridges and ravines onto a flat country which
gradually declines towards the sea. We could make out many villages
and much cultivation on the slopes from the deck of our ship. The southern
mountain range has no such level land declining toward the sea, but
the plateau (400-500 feet in height) continues towards the southwest.
It consists of completely horizontally layered strata, whose intersecting
lines continue horizontally along the coast and are visible for a long
distance because of the sparse vegetation. The slope towards the sea
cuts them off quite abruptly, but on closer inspection one can see
a large number of small gorges and valleys, which interrupt the continuity
of the slope. The seemingly level plateau dissolves into a hill country,
whose irregular formation but regular height makes the profile seem
horizontal. Between the two mountain massifs the continuation of the
plateau is only visible in two slopes, which are somewhat less steep than their upper counterparts
while embedding the broad canal of the Tamsui River. Further upcountry,
one can see mountain ranges in the distance.
The northeast coast is described as beautiful hill country; only in the distance
can one supposedly see a few higher mountains. The harbor of Kelung,
the only one on Formosa that is suitable for larger ships, is a small
indentation in this hill country and is protected from the north by
an island situated in the harbor.
Except for the region surrounding Tamsui and Kelung harbors, there is almost
no information on the surface formation and the composition of
the northern part of Formosa. Since the time of the Dutch settlement,
ended after rather short duration in 1662, European ships have
only occasionally visited some villages on the coast in recent
has been visited occasionally and was recently opened to foreigners
for very limited trade. Tamsui has only rarely been visited.
For years only a few small merchant vessels have been trading
this port and officially closed harbors in China, and therefore
one can usually see some European ships in the Tamsui harbor;
[p. 535] we found three of them. However, because visitors in
been either merchants or officers charting the coast, no one
was interested in continuing into the interior. The only one
who has seen the land
somewhat thoroughly is the Jesuit priest De Mailla, who in April
and May of 1714 made an astronomic chart of the western side of the island for the Chinese government. Of the more recent
travelers, only Mr. Swinhoe from Amoy has undertaken a short
excursion (in 1858, of 55 hours), starting from Kelung (3). In
addition, the captain
of an English trade brig told us that he had sailed 40 sea miles
upstream on the Tamsui River on his ship. From the coinciding
reports of these
two last investigators it becomes clear, as is already stated
on the newest maps, that the Tamsui River is created from two
sea miles above its discharge into the ocean (which is beyond
the effect of the tides), of which the smaller river runs from
the east and passes
closely by Kelung, but, as is indicated, does not constitute
a canal to that port. Swinhoe followed this river upstream, and
great difficulties because of the numerous cataracts. In the
end he arrived in a broadened basin that is only fed by mountain
streams. The surrounding area was wild and rocky. From that basin,
only two English miles across the hills. According to the indications on newer maps, the Tamsui River has
a very long course, and is navigable for small sea ships as long
as its course in a southeastern direction, which amounts to not
quite 40 sea miles. Thirteen miles upstream there lies the city
with its 20,000 inhabitants. The land there is supposedly extraordinarily
fertile and therefore fuels the prohibited trade from the Tamsui
harbor with China with the value of its products.
2. Mining in the Tamsui harbor.
The Tamsui harbor is at the estuary of the Tamsui River, where it broadens into
a basin and is still fully affected by the tides. Our ships landed
not far from the small town of Ho-bi [Hoowei], a short distance from
the intersection of the two mountain massifs mentioned above. The land
between these peaks and the level region that stretches toward the
sea (in which the harbor is set) is part of the hilly slope that gradually
stretches toward the sea from the mountains. My investigation had to
be limited to this part of the Tamsui region because the shortness
of the stay precluded a more thorough inspection of the massifs above.
There was a lot of data available in this foreland, which helped me
ascertain some geological facts. The investigated rock specimens belonged
to two different series, of which one is connected to trachyte outcroppings,
while the other belongs to later formations.
A. Rocks from the trachyte period.
1. Trachyte. If the very formation of the two massifs already indicated their
composition as being from trachyte and trachytic friction conglomerates,
this was certain for the northern blocks, which have come down in masses.
There can be almost no doubt that the southern counterpart consists
of the same rock types. The blocks belong to two different kinds of
trachyte. The first kind, which dominates, is a hornblende-oligoclase
trachyte without sanidine or augite, a fairly common middle-level rock.
The fine-grained grey basic material recedes against the mass of enclosed
crystals. The hornblende is dark red-brown, extremely petalled, and
forms small pillars of 2-6 lines in length. Their arrangement is very
strange. When the rock is broken, on some of the exposed surfaces one
can see the shining breaking points of the crystals weaving into each
other from all directions, similar to what is seen in an actinolite
slate. In contrast, on the exposed broken surfaces arranged vertically
to these, there are hardly any broken crystals. Therefore, the axis-surfaces a b have to be more or
less parallel throughout the whole rock, whereas of single axes only
c has the same direction throughout the stone. [p. 537] The oligoclase
is greenish-white; its crystals are smaller than those of the hornblende.
Regarding their arrangement, they follow a similar pattern. On the
same broken surface, on which the shining breaking points appear on
the hornblende, one sees evenly rounded, dimly shining surfaces of
the oligoclase, while on the horizontal cleavages, there are oblong
intersections, for the most part not shiny. Both minerals give this
trachyte an extremely characteristic imprint. Next to these there are
also green, hard mineral inclusions that become visible only after
closer inspection. The entire rock has an irregular fragmentation;
it breaks easily and in the direction in which the breaking surfaces
of the crystals lie, but it breaks with difficulty, usually splintering
in the other direction. The weathered layer is double: the outer layer is rust-brown and paper-thin, while the inner one
is dark reddish-brown and as thick as a line; both are clearly distinguishable.
The second trachyte is basalt-like, very brittle; it breaks into flat bowls and
sharp-edged pieces and only consists of a grey-black, fine-grained
mineral mixture, in which are found irregular brittle crystals of dark
leek-green, translucent augite. The weathered layer is the same as
in the above type, but the outer cover is more yellowish-brown.
I could not discover in which combinations the two trachytes appear. It seems
to me that there are additional variations, but all of them are more
2. Rough trachytic conglomerate. In several places along the coast near Ho-bi
one can see a rough conglomerate that constitutes the basis for all
further sediment formations of the hill country. It includes jagged
fragments of different trachytes in a sturdy trachytic mass. This conglomerate
is possibly an eruptive mass that melted and then solidified into one
layer and would then be included into the category of formations that
are most fittingly called eruptive tuffs [whine stones]. The base rock
is too sturdy to be merely sedimentary, and the spread is too even
to be only eruptive. The level on which the rocks become visible is
overall the same; one finds them only on the coast, which is then covered
by blocks because of the weathering that occurs. Such a sea of stones
lies at the end of a huge sand barrier, which the Tamsui River has
accumulated in its estuary.
3. Trachytic tuffs, weathered to a reddish-brown, earthy mass. Nowhere did I
find these tuffs in their original form, even though they formed the
whole hill country over the level of the above-mentioned conglomerates.
However, one can still clearly see the structure of the rocks and the
horizontal layering. Some layers are filled with trachyte blocks that
are weathered to an equally earthy mass as the binding agent, but are
distinguishable because of their yellowish-white coloring and the denser
bonding of the decomposed mineral mixture. The huge size has to coincide
more or less with the height of the hills, first of the slope of the
trachyte mountains, which rise about 400-500 feet. These decomposed
tuffs are the reason for the fertility of the area around the harbor
of Tamsui. The uneven plain of the slope is covered with fields; flat
valleys with soft slopes are sunken into the hill country. The ground
is leveled by humans, and terraced into rice fields. In addition to
this main staple crop farmers also grow all kinds of grain, cotton, sweet potatoes, yams, sugar cane and
other useful products, and only the limited area precludes great harvests.
The three formations from the trachyte period almost exclusively compose the
area around Tamsui harbor. The tuffs seem to spread out very widely.
The regularity of the mountain massif formation and the unhindered
horizontal layering make it more than probable that the entire expansive
plain, which stretches lengthwise along the coast southwest of Ho-bi,
is formed of tuff layers. As noted above, its horizontal layering is
visible in the layering surfaces, which cut through the sea in horizontal
B. Recent formations.
Recent formations play a rather subordinate role, but give some indication of
the current geological processes taking place along the coast and of
the geognostic construction of areas farther away. These formations
are also threefold: gravel, dolomite banks and sand.
4. Gravel. This consists of fully rounded tills that are cemented together through
a chalk and clay-like binding agent and form rough terraces of up to
30 feet in height situated at the bank below Ho-bi. The main constituents
of this formation are the same boulders that the river still carries
with it: trachytes of different kinds; rough-grained granite from grey
quartz, reddish orthoclase, black glimmer in deep boards and very sparingly
scattered yellowish-green oligoclase; but especially rough-grained
white, yellow and light-red quartz sandstone. This latter stone is
found in great blocks, which indicate that it originates from not too
far away. I did not find crystalline slate and chalk.
5. Shell breccias are located on the slopes of the tuff hills everywhere up to
a height of a little more than 100 feet. The binding agent of the loose
rocks is the ocher-colored sandy earth. Most of the graves in this
area are situated on this bank.
6. Sand seems to be the youngest formation. It constitutes the anchorage in the
harbor, the banks in the river, the barrier that separates the harbor
from the sea, and it covers the trachytic conglomerate on the right-hand
bank of the river estuary in the form of infertile hills that are often
only covered with pandanus.
[Here the original text includes a rough sketch of the typical profile on the
Tamsui River. It shows sand and trachytic conglomerate near the seashore,
gravel further up the slope, followed by trachytic tuffs and shell
breccias higher on the hills, with the mountain top covered with trachyte.]
The mutual stratification relationship of the rocks described here can be seen
in the above typical profile of the geological formation of the hills
on the Tamsui River. [p. 540] One can see the complete chronological
order in almost any ascent from the river to the heights; only the
valleys usually lack the recent formations.
The developmental history of the small area we are concerned with is clearly
visible in the described composition. The trachytic mountains, the
trachytic friction conglomerates and the tuffs belong to an earlier,
probably tertiary period, after which the land rose and the river bed
was formed. The depression was only formed in a fairly recent period,
but the terrain must have at least reached up to the surrounding heights,
to which the recent formations extend on the slopes. The broadly eroded
riverbed was filled with the boulders that the river carried down,
and in the last periods of the lowering process (when the brackish
waters, moved by the tides, washed around the slopes of what now are
the tuff hills), the river sand was deposited with the earthy destructive
products of the tuffs and mixed with the fragments of the shells on
a higher level than the gravel banks. At this moment there was another
upheaval in this region. Again the river dug its bed deeper into the
material that it had deposited itself. Then the atmospheric waters further eroded the slopes and removed the cover
lying on the tuffs in many places, until the only thing left were the
recent formations that we can see today on the slopes. The river now
covers the flatter portions of the exposed areas with boulders and
sand. The sand dunes have already partly become flat hills above the
level of the sea, and they are rising further and further above it.
3. Massif formation in the harbor of Kelung.
We are in possession of a valuable report about Kelung written by Mr. Jones,
ship chaplain who accompanied the Macedonian, one of the ships that
Commodore Perry sent to Kelung in 1854 in order to investigate Formosa's
coal. Unfortunately, Mr. Jones focused completely on the description
of the coal seams, their strength, stroke and fall and only mentions
in passing the fact that the entire hill country near Kelung consists
of sandstone, in which the coal is embedded. [p. 541] One could think
that this was a continuation of the considerable accumulations of quartz
sandstone, whose fragments can be found in boulders in Tamsui. However,
it is more likely that this is tuff sandstone. Jones describes a place
called Image Point, a protrusion of the land that received its name
because of the weathering of the layered stone into the shape of baroque
figures. The base rock formation of these figures consists of a brown
sandstone topped with rounded large black stones. A sketch [by Jones]
shows that they are similar in shape to the earth pyramids of Botzen: thin long cones, upon each of which
sits one of these black stones. These latter ones are probably darker
trachyte in this area so marked by trachyte, and the whole formation
seems to belong to the tuff mountain massif.
This is unfortunately all that Mr. Jones says about the geognostic composition.
We owe two interesting facts to the Kelung harbor sailing rules compiled
by Lieutenant Preble of the Macedonian. These rules state that Kelung-khid,
or Kelung Island, is a small volcanic isle, 500-600 feet in height,
located in the entry to the harbor. Jones says that the island consists
of syenite. Whether this is accurate remains to be seen. Furthermore,
Preble writes that the flat island called Tong-fung-si (Collinson’s
Bush Island) is covered with a layer of old corals; it is located on
the east end of the harbor, which was supposedly raised up from below
sea level along with the underlying sandstone.
Coal bed of Kelung. For a long time, there had been uncertain accounts of fossil
fuel in the northernmost part of Formosa. As much as the exploitation
of coal in a place so much closer than England was desirable, especially
when taking into account the growing steamship traffic in the East
Asian seas, there had been no trustworthy investigation of Formosan
coal. Perry gave the Macedonian certain instructions regarding this
question, and we owe the following description of the Kelung coal bed
to Mr. Jones's report. In July, 1854, the coal beds east of the harbor
were investigated, and a small map was made. In spite of the obstructions
to travel beyond the harbor, Jones arrived at his destination. [p.
542] According to him the beds begin close to the harbor and stretch
from there eastwards, where one can find them in the small bays of
Qua-se-ku and Kea-lau. The identified seams begin on the surface and
were mined from there on inwards; a large number have turned out to
be extractable. Whether it is hard or brown coal is not reported, but the latter is more probable. According to
tests that Commodore Perry ordered, the Formosan coal turned out to
be of a lesser quality than the "best" English coal, which was the only [English] type it was compared to, but much
better than the Japanese product, which is not a great achievement.
It burns quickly, but there is surprisingly little residue. The costs
of exploitation for a ton of twenty hundredweights would be one and
one-quarter dollars; the conveyance from coal bed to ship would hardly
add any expense at all because of the proximity of the island's best
harbor. Therefore, the price comparison to English coal would seem
extraordinarily advantageous, since English coal is traded in Shanghai
at 69 shilling or 15 dollars a ton. Everything said in the American
report about Formosan coal should lead one to think that it has a very
bright future. Until the date of the report (1854), this coal was only
extracted to a very limited extent, according to the needs of the inhabitants.
It was never exported or even sold locally to ships, and even the Macedonian
could organize a sale (100 hundredweights for 16 dollars) only through
tricks. Since that time, seven years have passed. At first, one knew of the existence of this Formosan
coal; now one has more certain knowledge, and yet we are still dealing
in Kelung coal from Chinese port cities. However, Formosan coal has
still not been able to compete with English coal even in East China.
She shares a fate with Nagasaki coal, which has similar traits, and
yet is better than Yokohama coal (and this latter type was the one
that Perry used in his comparisons). From Nagasaki and from Kelung,
Chinese junks bring coal to Shanghai and sell it to the Chinese. However,
steamships prefer the English coal in spite of the price that is four
to five times higher, and only sailboats that also use a propeller
make use of the brown coal of both harbors. [p. 543] It is the same
as the coal of Labuan near Borneo and other Sunda Islands. The brown
coal can't compete with the most expensive hard coal.
While Jones only investigated the coal beds to the east of the harbor, Swinhoe,
who visited the harbor four years later (in 1858), writes only of coal
beds west of the harbor in a bay:
These mines are worked by Chinese, who live at their entrance in huts built of
straw and wood. There are eleven or twelve excavations, their
mouths opening out, at different heights, on the side of a
hill facing the
sea. I went to the end of one, guided by a man bearing a lighted
piece of twisted paper. The excavation, which ran in a horizontal
direction, varied from about four and a half to three feet
in height and three to ten feet or more in breadth. The strata
of coal run
along on both sides in parallel lines from one to three feet
in thickness. The roof above, and the floor underfoot, were
composed of sandstone.
Water was constantly dropping from the roof, and this mixing
with the sand formed a slimy mud. The hole ran in pretty nearly
in a straight
line for two hundred and forty paces; at the end it took a
sudden turn to the right. Small wicks in saucers of oil lighted
along, and we found five or six men at work in a state of nudity
with pick-axes, blunt at one end and sharp at the other. The coal which they obtained was very small and bituminous, and burns fast but
with a great heat and flame. It is very certain that they get
the best there is in that locality. They asked twenty cents
a pecul for
it, and declared that five men, at work in a mine for twenty-four
hours, did not procure more than thirty baskets, containing
a pecul each(4).
When one takes these reports together, it seems that coal is common around Kelung,
and forms several seams between one and three feet wide that are worth
exploiting, but those coal beds are also included in tuff sandstone
and it is a tertiary brown coal.
4. The Sulfur mines between Tamsui and Kelung.
Sulfur is one of the most important export products of the northern harbors of
Formosa. Until a few years ago, it was unknown where this sulfur was
collected; now it has become known that there are sulfur mines on the
northern tip of the island, [p. 544] exactly on the north side of the
higher of the two mountains near Tamsui. Swinhoe is probably the only
European who has visited the mines (in 1858). He found them deserted,
even though they had been heavily worked shortly before. The mandarins
of Fokien had sent soldiers to prevent their exploitation, and now
the mines can only be worked secretly. Swinhoe wrote the following
The sulphur was produced in a chasm, appearing as if the green hills, covered
with coarse grass, had been riven in sunder, thus forming a
deep valley of limestone tinted with yellow and red; in some
this chasm the hot steam was gushing out in jets, with tremendous
noise and force, like the steam from the escape-pipe of a high
pressure engine; in other spots small pools of pure sulphur
and merely wanted the ladling out and cooling to form the sulphur
of commerce. At the bottom of the barren ravine rippled a foul
rivulet, carrying off the sulphureous oozings from the ground.
the top of a hill, I looked down upon the scene: one sulphur
pool was not more than fifteen feet below me, and its stench
the earth under foot crumbled and groaned, as if it were going
to give way; pieces of limestone, covered with the crystals
of sulphur, lay strewn about; while beetles and butterflies,
to the noisome exhalations, were scattered wingless and legless
ove r the ground(5) .
At the same location of these sulfur mines, Klaproth located one of the four
active volcanoes on Formosa. From Swinhoe's description it seems to
become clear, however, that there are only remainders of volcanic activity
here, and more precisely a solfatara instead of an active volcano.
The most general conclusions can be summarized as follows: The northernmost part
of Formosa in its interior consists of older rocks (of which numerous
fragments are washed away in the Tamsui River) and of trachyte. Near
the coast the land seems to be exclusively composed of tertiary eruption
products, which in part loom in high trachytic mountains, and in part
spread out further from these mountains as eruptive tuffs, [p. 545]
and form a mighty system of sedimentary tuffs. The latter constitute
a far reaching hill country that surrounds the trachyte-mountain range
near the Tamsui border, stretches to the southwest as a low-lying plain
to Namkan Point and Paksa Point, and probably forms the entire area
around the Kelung harbor, including the coal beds there. There are
traces of former volcanic activity that continue in their last stages
in the sulfur mines near the northern tip of the island.
The recent formations point to the fact that the island is currently in the process
of a slow upheaval, similar to that of the Liu Kiu Islands and Kyushu.
1. On the maps one finds in the middle of the island a mountain indicated as
Mount Morrison, 10,800 feet high, and to the north a mountain
with no further designation at "about 12,000 feet." No European has ever been near these mountains. The latter height estimate stems
from Mr. von Humboldt, who concluded that the absolute elevation
was at least 11,400 feet (1900 toises [1 toise = 1 949 m]) from
that the highest mountains in Formosa are covered with snow for
most of the summer. I could not find out where the height estimate
Morrison came from.
2. Usually, four active volcanoes are specified on Formosa, because of a statement
made by Klaproth, who received this information from Chinese reports on Formosa.
But until this statement has been affirmed by travelers, one should treat it
very seriously, since mistakes are very likely in the interpretation of Chinese
sources, especially regarding the "Fire Mountains." I will try to show that for one of these cases on the northern tip of the island
there certainly is a wrong interpretation.
3. This was reported in the Journal of the North-China branch of the Asiatic
Society, Volume 1, Number 2, May 1859.
4. Translator's note: This section is quoted directly from Robert Swinhoe, "Narrative of a visit to the island of Formosa," Journal of the North-China Branch of the Royal Asiatic Society 1, ii (1859):
5. Translator's note: This section is quoted from Swinhoe, 1859,