The Boy Travellers in South America. Thomas Wallace Knox
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is the only one on which there has been an attempt to make a canal; the government of the United States has made a treaty with Nicaragua for the construction of a canal through that country, but, up to the present time, the scheme has not gone beyond the surveys and the reports of the engineers."
"We are confident," said Mr. Colné, with a smile, "that our canal from Aspinwall to Panama will be completed, and that large ships will pass through it before the 1st of January, 1890. Indeed, some of our engineers promise it for the New Year of 1889. Thus far the work has progressed quite as fast as we expected at the outset, and if no unforeseen difficulties arise, we shall have the canal completed before 1890."
One of the youths asked how much the canal was likely to cost, and how it would compare with the Suez Canal, which they had visited on their return from the Far East.
"Not to trouble you with details," replied the Doctor, "the estimate of the cost was originally six hundred millions of francs, or one hundred and twenty millions of dollars. Very few enterprises come within the original estimates, and it is probable that not less than thirty millions of dollars, and perhaps another hundred millions, must be added to these figures, and some engineers say three hundred millions will be required. The cost of the Suez Canal was about one hundred millions, and the work at Suez was very light compared with that at Panama."
"I remember," said Fred, "that the Suez Canal is practically a great ditch through a sandy country, with no elevation of more than sixty feet, and but very little rock to be cut away. Nearly half the length of the canal was made by filling up depressions in the desert, which were turned into lakes by allowing the water to run into them. Is there anything of the kind here?"
"Not by any means," was the reply; "the Panama Canal is being cut through a region where the difficulties are enormous by comparison with those at Suez. Instead of a waste of sand, there is a tropical forest for the greater part of the way, and in place of the depressions which were converted into lakes to form part of the Suez Canal, we have a chain of hills which are nearly three hundred feet high at the lowest points. The summit level of the Panama Railway is two hundred and sixty-three feet above the level of tide-water on the Atlantic coast, and the canal must have the enormous depth of three hundred feet, and at some points more than that."
"That is quite correct," replied their host. "It will be the deepest canal cutting in the world when it is completed. On the section of Culebra, in a distance of little more than a mile, we must remove twenty-five million cubic metres of earth and pile it up elsewhere. Fortunately, our work is rendered easy in this respect, as there are many valleys close to the canal where the earth can be disposed of. Do you know how much is represented by twenty-five million cubic metres?"
Fred made a calculation on a slip of paper, roughly converting metres into yards by adding one fifth. Then he reduced the yards into cubic feet, and announced that, with the earth to be removed from the Culebra section of the canal they could build a wall nine feet thick and twenty feet high for a distance of twenty-eight miles, and have a good many car-loads to spare.
"This will give you an idea of the work to be performed here," replied Mr. Colné, "and you must remember that it is only one single section of the entire line. Then, too, there are great difficulties in the way on account of the rains, and the sudden overflows of the Chagres River, which crosses the line of the canal. Instead of being a depression to be filled with water, it is liable to pour out at any moment much more water than we want."
"The average rainfall of this part of the Isthmus," said Dr. Bronson, "according to the official reports, is over twelve feet. This is not distributed through the year, but is confined to about seven months. During a single rain-storm six and a half inches of water have fallen.
"The consequence is that there are excessive floods in the rivers; the Chagres River, which you see represented on the map as crossing the canal, is, in the dry season, a stream about two hundred and fifty feet wide and two feet deep. During a heavy flood it is fifteen hundred feet wide, and over forty feet deep, and it has been known to rise thirty or forty feet in a few hours. In these floods it brings down trees, rocks, and earth, and sometimes houses, and the sides of hills. In one freshet, an iron tank, that stood seventeen feet above the railway track, was washed away, and on several occasions considerable portions of the road have been destroyed."
"We get over that difficulty," said Mr. Colné, "by making a barrage, or dam, across the river, and between two hills, to retain the waters during the freshets, and let them out gradually by lateral sluices. The capacity of the reservoir formed by the dam will be much more than enough to hold all the water coming down in the greatest rise that has ever been known since the railway was completed, in 1855. Mr. De Lesseps says that there are three reservoirs in the world of greater capacity than this: one is at St. Etienne, France; one at La Gillappe, Belgium; and one at Alicante, in Spain. They have stood for three centuries, and are as good and strong as they ever were. Science has improved since the great retaining walls of Alicante were erected, and the dam of the Chagres River will be perfectly safe, and do justice to the science which constructs it."
By this time the boat had reached the line of the breakwater which was being constructed to protect the harbor from the strong "northers" that sometimes blow at Aspinwall, and make anchorage unsafe. The earth dredged from the canal and from the shallow portions of the bay was partly used for forming the ground already mentioned, and partly for constructing the breakwater. For the latter purpose it was piled between walls of rock, and it was expected that the work would be completed long before the canal was ready for use.
From the breakwater they were taken to the entrance of the channel opened by the dredges for the canal, and the location of the proposed new port was pointed out. Then they proceeded up the great ditch for two or three miles, and landed where the canal and railway were close together. Two hand-cars were standing on the track and evidently waiting for them. The gentleman to whom they had brought the letter was there, and also one of the officials of the railway. At the invitation of the latter, the party was soon distributed on the vehicles, three on one and three on the other. Comfortably seated on the front of the hand-cars, which were propelled by natives in very scanty dress, our friends rolled easily over the level track, in the direction of the high ground, and also of Panama.
Frank and Fred thought they had never taken a more delightful ride. The air was delicious; there was the luxuriant vegetation of the tropics all around them; birds were abundant in the trees; monkeys occasionally chattered above them, or swung from the limbs, as if inviting the strangers to stop and visit their relatives; the speed was just enough for comfort; their vision was unimpeded, and there was no locomotive in front of them to poison the air with fumes of burning coal or shower them with cinders. Then, too, their guide was a cyclopædia of knowledge, as he had been for a long time connected with the railway and was thoroughly conversant with its history.
"It was one of the most difficult roads to build that I ever heard of," said he, "and three times the work was suspended on account of the impossibility of getting enough laborers or bringing forward the necessary material. Everything had to be brought from New York or some other American or European city, as there was no labor worth having to be found on the Isthmus itself. Between Aspinwall and Monkey Hill the engineers had sometimes to wade up to their waists while laying out the line, and after the road was completed the track repeatedly sank down out of sight. It happened several times that two or three hundred feet of road would thus disappear in a single night, and then the