"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." [Illustration: IN THE RAINY SEASON.] "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. [Illustration: A HAND-CAR JOURNEY ON THE PANAMA RAILWAY.]