REPORT OF BOARD OF CONSULTING ENGINEERS, PANAMA CANAL. T


locks on the Pacific at the shore line at Sosa should be deemed inadvisable and the location at Miraflores, three and six-tenths miles inland, be substituted, the cost of the canal would be increased about $8,000,000.
 COMPARISON WITH THE BOARD'S LOCK-CANAL PROJECT.
 The project for a canal with summit level at elevation 60 is fully described in the report of the Board. The principal differences between the two projects are:
 The lower summit level in the project preferred by the Board.
 In the Board's proj et the Gatun dam is to sustain a head of only 30 feet and the level above the dam is to be reached from the sea level by a single lift, duplicate locks being provided. Another dam and duplicate lock with equal lift will be located at Bohio, maintaining the summit level. There is to be a suitable wasteway in connection with each dam..
 The low elevation of the summit level in the Board's project makes it necessary to regulate floods by building a dam on the upper Chagres, and the smaller size of the lake above the Bohio dam also requires the storage of additional water for lockage. The Board proposes to meet both of these requirements by a dam at Gamboa identical with that adopted for the sea-level canal.
 In the Board's project the summit level is to be reached from the Pacific by two lifts instead of three, the locks being located at Pedro Miguel and Sosa, with the intermediate level at elevation 27.
 The advantages of this project are:
 1. The smaller head of water to be sustained by the dams at Gatun and Bohio than by the Gatun dam in the 85-foot project.
 2. The smaller height of embankments required to maintain the intermediate level between Pedro Miguel and Sosa, the water surface being 28 feet lower.
 3. The summit level would be lower and the locks reduced in number from six to four; there being no flights of two or more locks, but only a single lift at each locality, a transformation to a sea-level canal could be effected more readily.
 4. The great lake to be formed by the Gamboa dam would afford control of the floods of the Chagres with less fluctuation of water in the canal.
 5. The spillways would be smaller structures.
 The disadvantages of the summit-level project preferred by the Board are:
 1. The greater number of lock locatons-at four points instead of three-which would require, until traffic becomes large, a little more expense for operation.
 2. The greater number of dams and spillways on the Atlantic side, being three instead of one; one of the dams, that at Gamboa, far exceeding the Gatun dam for the 85-foot summit level in height and head of water sustained.
 3. The great reduction of channel width, giving a canal less favorable for navigation.
 4. The greater time required to build, estimated at two years.
 5. The greater cost, estimated to be about $36, 000,000.
 The following table, classifying the channels of the two projects with regard to width and giving the proportion of each width, shows the great superiority for navigation of the canal with summit level at elevation 85.
 Proportion to entire
 length of route.
 Width of channel. Sumt umi
 elevation elevation
 60. 85.

 Per cent. Per cent.
 1,000 feet.................... 00 38.4
 800 feet -_------------------- 0.0 7.8
 500 feet-------------------- 26.4 24.7
 300 feet.....................-- 52.1 14.5
 200 feet...................... 16.2 9.4
 Locks and approaches .... 5.1 5.2 Total----------------- 100.0 100.0


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