REPORT OF BOARD OF CONSULTING .ENGINEERS, PANAMA CANAL.


on 500,000 cubic yards of concrete; that is to say, on about less than 750,000 tons of stone, sand, and cement for each twin lock of 35 feet fall. As there are eight twin locks in the plans I propose, the total mass to be transported within three years would be 6,000,000 tons, or 2,000,000 tons per year, or 7,000 tons per each of the 300 working days. This would lead to the formation at Colon of seven trains of 1,000 tons daily, a figure which is perfectly admissible for the section of the road situated in the valley of the Chagres. Trains would have left half of their load when leaving the easy gradients of the Chagres Valley, and the same engines could easily pull the remaining cars to the other side of the Isthmus.
 Any man familiar with the magnificent results obtained on the Great Lakes for handling on ship, from ship to car, and on cars, large masses of material will state that these figures have nothing abnormal. By this method the three elements of the masonry of the locks would come to their destination without having borrowed practically any element from the precious and rare isthmian labor, which must be jealously kept for the isthmian operations proper.
 Of course, to this amount has to be added the mass necessary for the Gamboa dam, but it will play a relatively minor part compared to what is necessary for the bulk of the eight large twin locks of the canal.
 TIME OF CONSTRUCTION OF THE LOCKS.

 The question of construction of locks is thereby reduced to the excavation of their sites and the depositing of concrete afterwards. To make the concrete simply consists in digging into deposits of stones, of sand, and of cement, loading light hand cars (two-thirds cu. yd. capacity), and in dumping them with the necessary quantity of water. into tubes, from the other end of which the formed concrete falls in its place.
 Being given the extreme simplicity of these operations and the large extension of the sites of the locks, it is extremely conservative to suppose that at every lock, say on each of the 16 locks (or S twin locks), a mass of concrete of 400 cubic yards may be deposited daily without any difficulty by a force of 200 men. This would make 800 cubic yards per each twin lock with 400 men, or 240,000 cubic yards per year. The depositing of the concrete would be then made within a little more than two years with a force of about 3,200 men.
 It is easy, therefore, to see that under such a plan the realization of the locks within four years can be accomplished. If we devote two years for the excavation of the sites of the locks, and if the depositing of the concrete is started at the heads so as to finish with the heads within half a year, the erection of the gates will have one and a half years in which to be completed, which can be very easily done if the gates come from the States divided into large pieces of 10 tons or more, necessitating as little riveting as possible on the Isthmus.
 Of course, in operating the canal the gates must be handled both by hand and by hydraulic or electric machinery. It does not enter in my four years' programme to have installed but the hand machinery. The more perfect machinery is not necessary at the beginning and will be erected later. The only difference between the time for the Bohio locks and the others is that their sites will be occupied one year by the deviated Chagres; therefore they must be done in three years instead of four, which I think perfectly practicable.

MARGINS OF SAFETY GIVING FULL GUARANTY THAT THE OPENING OF TRAFFIC WITHIN FOUR YEARS CAN BE SURELY ACCOMPLISHED.

 As the President of the United States expressed it so justly to the Board of Consulting Engineers, the moment when the first ship will pass from ocean to ocean can not come too soon; this will be the day of the victory over nature. Now, it matters very little whether on that day the works are completely finished or not, as the traffic of 6 million tons that will pass during the first years does not necessitate the ample dispositions provided for. This traffic will correspond to an average passage in each direction of one ship every twelve hours. For such a small traffic the canal may be opened with a bottom width of 100 feet instead of 150. For such a small traffic the canal may be opened with one lock instead of two, if the upper head of the other one is


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