South America Observations and Impressions. Viscount James Bryce
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of the northern. After five miles of comparatively shallow cutting southward from the Lake, a tall and steep eminence, Gold Hill, the continental watershed, its top 665 feet high, bars the way. Through it there has been carved out a mighty gash, the "Culebra Cut," of which more anon. A little further south, eight miles from the Lake, the ground begins to fall rapidly towards the other sea, and we reach the fourth or Pacific section at a point called Pedro Miguel. Here is a lock by which the Canal is lowered thirty feet to another but much smaller artificial lake, formed by a long dam built across the valley at a spot called Miraflores, where we find two more locks, by which vessels will be lowered fifty-five feet to the level of the Pacific. Thence the Canal runs straight out into the ocean, here so shallow that a deep-water channel has been dredged out for some miles, and a great dyke or mole erected along its eastern side to keep the southerly current from silting up the harbour. From Pedro Miguel to Miraflores it is nearly two miles, and from the locks at the latter to the Pacific eight miles, so the length of this fourth Pacific section, which, unlike the Atlantic section, is on two different levels divided by the Miraflores dam and locks, is ten miles. In it there has been comparatively little land excavation, because the ground is flat, though a great deal of dredging, both to carry a sea channel out through the shallow bay into the open Pacific, and also to provide space for vessels to lie and load or discharge without blocking the traffic.
Thus the voyager of the future, in the ten or twelve hours of his passage from ocean to ocean, will have much variety. The level light of the fiery tropic dawn will fall on the houses of Colon as he approaches it in the morning, when vessels usually arrive. When his ship has mounted the majestic staircase of the three Gatun locks from the Atlantic level, he will glide slowly and softly along the waters of a broad lake which gradually narrows toward its head, a lake enclosed by rich forests of that velvety softness one sees in the tropics, with vistas of forest-girt islets stretching far off to right and left among the hills, a welcome change from the restless Caribbean Sea which he has left. Then the mountains will close in upon him, steep slopes of grass or brushwood rising two hundred feet above him as he passes through the great Cut. From the level of the Miguel lock he will look southward down the broad vale that opens on the ocean flooded with the light of the declining sun, and see the rocky islets rising, between which in the twilight his course will lie out into the vast Pacific. At Suez the passage from sea to sea is through a dreary and monotonous waste of shifting sand and barren clay. Here one is for a few hours in the centre of a verdant continent, floating on smooth waters, shut off from sight of the ocean behind and the ocean before, a short sweet present of tranquillity between a stormy past and a stormy future.
In these forty miles of canal (or fifty if we reckon from deep water to deep water) the two most remarkable pieces of engineering work are the gigantic dam (with its locks) at Gatun and the gigantic cutting at Culebra, each the hugest of its kind that the world has to shew. The dam is nearly a mile and a half long; its base nearly half a mile thick, and it is 400 feet wide at the water line of the lake which it will support. Each of the three locks is double, so that one of the pair can be used by vessels passing from north to south, the other by those passing from south to north. Each has a useable length of 1000 feet, a useable width of 110 feet. They are big enough in length, width, and depth for the largest vessels that were afloat in 1911. He who stands inside one of them seems, when he looks up, to be at the bottom of a rocky glen, "a canyon of cement." Nothing less than an earthquake will affect them, and though earthquakes have been destructive in Costa Rica, two hundred miles away, there is no record of any serious one here. The locks will be worked, and vessels will be towed through them, by electric power, which is to be generated by the fall of the Chagres River over the spillway which carries its water from the lake to the Atlantic.
The great Culebra Cut is interesting not only to the engineer, but also to the geologist, as being what he calls a Section. It is the deepest open cutting anywhere in the world, and shows curious phenomena in the injection of igneous rocks, apparently very recent, among the loose sedimentary beds, chiefly clays and soft sandstones of the latest tertiary epoch. A troublesome result, partly of this intermixture, and partly of the friability and instability not only of the sedimentary strata but also of some of the volcanic rocks, has been noted in the constant slips and slides of rock and earth down the sides of the cutting into the bed of the canal that is to be. This source of expense and delay was always foreseen by those who knew the character of the soil and the power of torrential tropical rains, and was long dwelt upon as a fatal objection to a sea-level canal. It has caused even more delay and more expenditure than was expected. But it has now been overcome, though to avert the risk of future damage to the work when completed the engineers have been obliged to give a much lower slope to the sides of the cutting than was originally contemplated, so that the width of the cutting at the top is also greater than had been planned, and the quantity of material excavated has been correspondingly larger.5 In order to lessen further washing down, the slopes will be sown with creeping grasses and other plants calculated to hold the surface soil.
The interior of the Culebra Cut presented, during the period of excavation, a striking sight. Within the nine miles of the whole cutting, two hundred miles of railroad track had been laid down side by side, some on the lowest level on terraces along which the excavating shovels were at work. Within the deepest part of the cutting, whose length is less than a mile, many hundreds of railroad construction cars and many thousands of men were at work, some busy in setting dynamite charges for blasting, some clearing away the rubbish scattered round by an explosion, some working the huge moving shovels which were digging into the softer parts of the hill or were removing the material loosened by explosions, the rest working the trains of cars that were perpetually being made up and run out of the cutting at each end to dump the excavated material wherever it was needed somewhere along the line of the Canal. Every here and there one saw little puffs of steam, some from the locomotives, some where the compressed air by which power was applied to the shovels was escaping from the pipes, and condensing the vapour-saturated atmosphere.
There is something in the magnitude and the methods of this enterprise which a poet might take as his theme. Never before on our planet have so much labour, so much scientific knowledge, and so much executive skill been concentrated on a work designed to bring the nations nearer to one another and serve the interests of all mankind.
Yet a still more interesting sight is that which meets the visitor when, emerging from the cutting, he crosses to where, behind the western hill, are the quarters of the workers,6 with the cottages of the chief engineer and his principal assistants on the top. The chief engineer, Colonel Goethals, is the head not only of the whole scheme of construction but of the whole administration, and his energy, judgment, and power of swift decision are recognized to have been a prime factor in the progress of the work and the excellence of the administrative details. The houses, erected by the United States government, are each of them surrounded on every floor by a fine wire netting which, while freely admitting the air, excludes winged insects. All the hospitals have been netted so carefully that no insect can enter to carry out infection from a patient. Every path and every yard is scrupulously clean and neat. Not a puddle of water is left where mosquitoes can breed, for every slope and bottom has been carefully drained. Even on the grass slopes that surround the villas at Ancon there are little tile drains laid to carry off the rain. With the well-kept lawns and the gay flower-beds, the place has the air of a model village. And one sees the same in the other quarters of the employés all along the canal line, at Gatun, at Miraflores, at Ancon, where is the great hospital and where have been set up the offices of the civil government which does everything for its employés, both white and coloured. Nowhere perhaps in the world are workpeople so well cared for, and such ample and almost luxurious provision made for comfort and amusement as well as for health by the benevolent autocracy which presides over everything. Its success in escaping all charges of partiality or corruption, as well as in producing efficiency in the work and contentment among the workers, has indeed been such as to make some persons draw from it an argument in favour of State control of all great enterprises. To the unbiassed observer it is rather an instance of the efficiency obtainable by vesting full administrative control in men whose uprightness and capacity have already been proved beyond question, who have not risen by political methods, and who have nothing to gain by any misuse of their powers. So far as any political moral can be drawn from the case, that moral recommends
The highest point of excavation at Gold Hill is 534 feet above sea level and the highest elevation of the original surface of the ground along the centre line of the Canal was 312 feet above sea level. The vertical depth of the cut on the centre line is thus 272 feet, the bottom of the cut being 40 feet above sea level.
The unskilled labourers employed are mostly West Indian negroes from Jamaica and Barbadoes, with some Spaniards, but no Chinese. The skilled men are from the United States. Many Chinese were here in the French days and died in great numbers.