ON THE PRESENT CONDITION OF THE CULEBRA CUT, AND ON THE METHODS EMPLOYED
FOR EXCAVATION AND DISPOSAL OF THE SPOIL
REFERENCE once more to the plan and profile on the map will show at a
glance the length and position of the rocky divide, the whole of which
is termed the Culebra Cut, from the name of the town near the highest
point. The proposed form and dimensions of this cut, throughout the 5
miles of the greatest height, is also shown (the section adopted at the
commencement of 1906), and the stage reached in April, 1908, is shown by
the photographs. The line drawn across the above section at a level of
120 feet above bottom (160 feet above sea), shows the general level of
the bottom of the workings at Culebra itself at the time the photographs
were taken. A narrow pilot cut, only, was then 20 feet lower.
[Illustration: ROCK DRILL.]
[Illustration: ROCK DRILLS AT WORK IN THE CUT.]
All that part of the section below this line (+160) remained to be
excavated.
Most of the rock above this line has been removed, but not all, for the
final width is not, of course, reached at any level until the central
portion has been excavated below that level.
The level of the original rock line shown in this section was +275,
_i.e._, 235 above canal bottom, so that the photographs show excavation
of 115 feet of rock. There was, however, soil above the hard basaltic
rock, of varying thickness--removed to the slope 1:2 as shown on the
section. The highest original surface of the soil on the centre line of
the Canal (between Golden Hill and Silver Hill at Culebra) was +312
feet,[17] so that the photographs in which Golden Hill appears show a
total excavation of 152 feet along the centre line. As this line passed
along a saddle between the two hills, the original surface at the sides
was considerably higher, so that the total height shown in the
photographs from the bottom of the cut to the highest berm, or ledge, on
Golden Hill is considerably more than 152 feet.
[17] The profile at end of volume shows the stage of excavation
when the height here had been reduced to +210.
The bottom of the Canal will be 272 feet below the original saddle, and
its depth below this berm, which is seen on the photograph, is
considerably more. Thus will the gorge appear when the excavation is
finished and before the water is allowed to flow in. When full, the
surface of the water will be 227 feet below the original saddle, and the
passenger on a vessel will gaze upon the scarped banks of a somewhat
greater height than this.
For a tide-level canal, not only would the depth be 85 feet greater,
but, as the slope could not be made steeper, the width of the whole
cutting would be correspondingly increased.
With reference to the slope of the sides, it is important to note that
it has not been found practicable to adhere always to the proposed
section, which has to be made flatter, thus considerably increasing the
amount of excavation required. The behaviour of living rock is not
susceptible of the precise specification which can be applied to
quarried stone on the one hand or loose gravel on the other.
Mechanically it is complex, both on account of its structure and of the
_role_ which water plays in its economy. In the case of the Culebra
rock, the volcanic dykes by which it is traversed have altered the
nature of the rock in their vicinity, and the part played by water is
considerable, owing to the wetness of the climate. Moreover, the rock
does not remain wholly unchanged when exposed to air, but deteriorates
by "weathering," a chemical and physical process which proceeds much
faster in an equatorial climate than in the temperate zones. The
climate, however, has a compensating action, in so far as the rapid
growth of vegetation soon clothes and protects the scarped slopes, thus
acting as a "revetment."
* * * * *
Alighting at Culebra station on the Panama Railway, and proceeding to
the western side of the cut, one obtains the most impressive view of the
Canal works, and this is the spot usually visited by travellers and
tourists. I first stood there in January, 1907, and returned in April,
1908. The impressions obtained were very different on these two
occasions. In January, 1907, after two and a half years of American
occupation, what struck me most was the enormous mass of material which
had been removed by the French companies, and the comparatively
insignificant appearance of the American excavations, which could
readily be distinguished from the older work, already coated with
vegetation. It was then that I began to appreciate the heroic labours of
the French engineers, whose achievements under circumstances of great
difficulty are being daily more and more appreciated and praised by
their successors. Turning to study the progress of work, I watched with
delight the operations of the 100-ton steam shovels, which at a
distance, when the human hands are not seen, appear endowed with
volition, and remind the spectator of elephants at work. The cars were
loaded with surprising celerity, and the dirt-train was hauled off to
the distant dump by an old Belgian locomotive, part of the machinery
taken over from the New Company. But then the hitch came--there were no
cars to take the place of those already filled, and the steam shovel was
idle. Looking round, I found that many other steam shovels and their
crews were idle from the same cause, the machinery for transportation
not having been provided in proper proportion to the machinery of
excavation. That the time required for the completion of the rock-cut
was limited by the possible rate of transportation of spoil, and not by
that of excavation, had long been known, and the report of the Board of
Consulting Engineers contains elaborate diagrams of space available for
shovels and for tracks. It was apparent, therefore, that the
organisation of the work was not yet perfected. In like manner, as far
as I could judge during my first short visit, the West Indian labour was
not yielding the best results, owing to white foremen and coloured
labourers not being in perfect harmony.
[Illustration: THE CUT, LOOKING NORTH FROM CULEBRA.]
[Illustration: THE CUT, LOOKING SOUTH FROM CULEBRA.]
While, however, the fighting force, so to speak, of the Isthmian army
was obviously imperfect in many respects, great results had evidently
been achieved by the auxiliary services. The Department of Sanitation
had already made the Isthmus healthier than most equatorial countries,
food and quarters were excellent, law and order were well maintained.
On the first day of my second and prolonged visit, April, 1908, fifteen
months later, I went at once to the same spot on the Culebra Cut
opposite to Golden Hill and again surveyed the scene of operations. The
change was enormous. The gorge below me was greatly enlarged, the shape
of the hills altered, the face of the landscape changed. As I gazed into
the deep trench below, the thought flashed across my mind, "If my life
be spared a few years longer, I will sail through this on a ship."
The reason of the great change was readily apparent: organisation had
now been perfected. In the first place, the whole width of the cut was
laid down in railway tracks, tier above tier at the different levels, so
that the view was like the approach to the metropolitan terminus of one
of the world's great railways. Up and down these tracks there came and
went without ceasing the spoil-trains, now composed of larger trucks
than formerly, with new and ingenious devices for rapid unloading. The
number of steam shovels visible was much larger than in 1906, yet they
were kept constantly busy, and all the time the drilling machines were
at work boring holes for charges of dynamite, and gangs of men were
completing the preparations for explosions in other holes already
made.[18] Yet if the eyes were raised for a moment from the busy scene
below, they rested on a silent wilderness of tropical forest, stretching
unbroken to the horizon. I stayed until, at the approach of sunset, the
work of the shovels ceased, and hundreds of men swarmed out of the Cut,
and sought their quarters and the evening meal. But all was not over for
the day, for now, when the Cut was cleared, the shot-firing began. At
intervals there occurred a deafening explosion, the earth trembled as in
a considerable, but preternaturally short, earthquake, and masses of
rock rolled down the slopes, disintegrated and ready for the shovel-man
when he should arrive next morning. I paid many visits to the Cut,
between Empire and Pedro Miguel, but oftenest at Culebra itself. The
sight never palls, and is one of the wonders of the world. The Pyramids
are another wonder of the world which in common with many thousands in
all ages I have thought it worth going to see--but to go to Culebra is
as if one were privileged to watch the building of the Pyramids. Yet how
few go to the Isthmus on purpose to see these things, and, _mirabile
dictu_, how few Americans! How is it that this people, so enthusiastic
in all that relates to national achievement and addicted to foreign
travel, does not include the Isthmus among its many recognised places of
pilgrimage? Of the Americans whom I met on the Zone there was scarcely
one who had come voluntarily for pleasure. The hotel accommodation, it
is true, is limited, but it is more than sufficient for present needs,
and is good, as hotels in the tropics are reckoned. Moreover, Panama is
now one of the healthiest places in the Equatorial Zone. English
tourists going out to the West Indies by the Royal Mail are generally
able to cross the Isthmus and see something of the work while their ship
is unloading at Colon; but I would venture to suggest, to such of these
as care to follow the world's progress, that they should make
arrangements beforehand to step off at Colon, cross to Panama, put up
there, visit thence the Canal works at various points, and proceed by
their next ship. The West Indian tourist season coincides with the dry
season on the Isthmus. At Panama the mosquito is almost an extinct
animal, and though the heat there is sometimes trying, a run up to
Culebra brings one to a dry and bracing atmosphere where a fresh breeze
is almost always blowing.
[18] During 1908 no less than one million dynamite charges were
exploded.
The steam shovel is the principal agent of excavation. It scoops out
loose soil directly, but the basaltic rock has to be broken up first by
blasting. One shovel will load 1,200 cubic yards of such materials upon
the cars within the working day of 8 hours, an amount equal to 600
two-horse loads.
For accelerating transportation railway trucks provided with flaps are
used, which make of the whole train a single platform. At the rear of
the train is a plough which can be drawn by a wire rope attached to a
drum carried on a special car in the fore part of the train. When the
train arrives at the dump the drum is started, and the plough,
advancing, clears the 320 cubic yards of earth and rock from the 16 cars
in 7 minutes. This is the Lidgerwood Unloader.
Another important piece of machinery is the track-shifter, which picks
up and relays the railway lines of the ever-shifting spoil-tracks. This
remarkably successful contrivance was invented by an employee on the
Isthmus, and is moreover manufactured there in the great workshops at
Gorgona.
[Illustration: FROM CULEBRA, LOOKING EAST TO DISTANT HILLS.]
[Illustration: FROM CULEBRA, LOOKING EAST ACROSS THE CUT.]
From Bas Obispo to Pedro Miguel, which constitutes the Cut, is a
distance of about 9 miles, and excavation is so planned that a summit is
maintained at Lirio, near Culebra, about half-way between these two
points. On the north slope are[19] 21 steam shovels, loading cars on 14
tracks. These, when loaded, are hauled down-grade to the northern dumps
at Tavernilla and elsewhere, or to the site of the Gatun dam, which is
also a dump. Nearly 4,000 cubic yards of rock are carried to the dam
daily, a distance of about 24 miles. The return up-grade is made with
empty cars. On the southern slope about the same number of steam shovels
are at work, the spoil being taken to the southern dumping grounds on
the Pacific side, including the trestle dump for the breakwater to Naos
Island. The spoil-trains follow one another at intervals of about three
minutes, and if, from any cause, delay occur, the steam shovels, and
indeed the whole process of excavation, is brought to a standstill. Any
cause of delay is therefore reported at once by telephone to the
Superintendent of Transportation at Empire, and all energies are at once
directed to clearing the way. On the Isthmus everything gives way to the
spoil-train, as in a city to the fire-engine. An excellent lesson both
in the complexity and urgency of the transportation is afforded by a run
through the Cut on a motor trolley in company with the Superintendent of
the Department of Excavation. Constantly shunted from one track to
another, and occasionally having to retreat, much ingenuity is required
to thread a way among the spoil-trains, but even the almost invaluable
time of the Superintendent himself is sacrificed rather than any delay
should occur to the "dirt" train, as it is usually called. It is this
dirt which stands between the American nation and the realisation of
their long cherished scheme, and nowhere is the classical definition of
dirt as "matter in the wrong place" so appropriate as on the Isthmus.
[19] This is for July, 1908.
* * * * *
Let us now see how much matter has been removed, and how much dirt
remains which has yet to be removed. I will give first the totals of
what has been got out in both dry and wet way, both in the Canal prism
itself and for auxiliary works.
TOTAL EXCAVATIONS IN CONNECTION WITH THE PANAMA CANAL.[20]
Cubic Yards.
By the French Companies about 81,548,000
By the American Isthmian Canal Commission up to the
end of June, 1908 40,923,533
-----------
122,471,533
[20] Canal Record, July 8, 1908.
Much of the work of the French Companies, however, consisted in dredging
out sea-level channels at both ends of the Canal, whereas the principal
American work has been rock-excavation in the Culebra Cut--or _the_ Cut,
as it might equally well be called. The figures relating to the Cut
are:--
EXCAVATION BETWEEN BAS OBISPO AND PEDEO MIGUEL, _i.e._, "THE CULEBEA
CUT," 9-1/2 MILES.
Cubic Yards.
By the French Companies 22,600,000
By the American Commission to end of June, 1908 20,125,185
-----------
Total excavated in the Cut 42,725,185
Remaining to be excavated 37,973,063
-----------
80,698,248
so that at the end of last June the Cut was half cut through, one
quarter having been done by the French Companies and one quarter by the
American Commission.[21]
[21] The total excavation for the prism of a sea-level canal was
calculated by the Board of Consulting Engineers at 231,026,477 cubic
yards.
This statement by itself, however, would give a very inadequate idea of
the rate at which the excavation is now proceeding, for of the total
taken out by the Commission since 1904, 11,000,000 cubic yards were due
to the work of the 12 months prior to June last. It will be seen from
what has gone before that the rate of progress is now even greater than
in the year June, 1907-May, 1908, for the daily output from the Cut for
July, 1908 (55,427 cubic yards), works out at 1,441,102 cubic yards,
allowing 26 working days of that month, which, moreover, is a wet month,
when work is much retarded.
[Illustration: FROM CULEBRA, LOOKING EAST TO GOLDEN HILL.]
[Illustration: THE CUT AT CULEBRA, LOOKING NORTH.]
_On the Date of Completion of the Canal._
Colonel Goethals, Chief of the Commission, when examined early in 1908
at Washington, declined to bind himself to a date for completion, or to
an estimate of cost; nevertheless, it is not difficult to calculate the
date of completion from the actual rate of progress on the assumption
that all goes well. The year 1915 is thus arrived at by the authorities
for the calculated, though not promised, completion. This is based
primarily upon the rate of excavation possible under the restrictions
imposed by the narrow gorge along which the spoil has to be transported.
It has been also calculated that the constructive works, the locks and
dams, would require about the same time as, but not longer than, the
excavations. This just balance between the time required for the two
elements, excavation and building, was one of the arguments employed in
favour of the 85-foot-level canal, as securing "the utmost practicable
speed of construction"[22] which could be obtained in a canal
"affording convenient passage for vessels of the largest tonnage."
[22] See address by President Roosevelt to Board of Consulting
Engineers, September 11, 1905. Report of the Board, p. 12.
* * * * *
One of the most impressive features on the Isthmus at the present time
is the great workshop at Gorgona, where repairs of all kinds are done,
and large machines such as the track-shifter are actually built. As I
passed from machine shop to boiler shop, smith shop, car shop, pattern
shop, and so on, I felt myself back among the circumstances of one of
the great manufacturing towns, and forgot for the time my actual
surroundings. It was with a feeling akin to surprise that, on quitting
the foundry, I found myself on the fringe of the tropical forest, now
darkening with the shadows of the swift-descending sun. I may here note
by the way that the furnaces of the foundry produced considerable relief
from the effects of the tropical heat, which that day was somewhat
oppressive.
_Relaying the Panama Railway._
Reference to the map at the end of the volume will show how
considerable is the task of reconstructing the Panama Railroad--what
embankments have to be formed, circuits made, and (near Milaflores) a
tunnel bored. The track, too, is being doubled, and the rolling stock
has been greatly improved. The passenger cars are both comfortable and
relatively cool, and the double journey from Pacific to Atlantic Ocean
and back again can be pleasantly performed between luncheon and dinner.
Much of the verdant forest land on which I have gazed with so much
delight from the windows of the cars will soon cease to be land at all.
It will be drowned beneath the waters of Lake Gatun; virgin forest,
cultivated patch, squatter's hut, villages, and even small towns will
disappear, their sites submerged by water, and presently to be covered
by the silt of rivers.