REPORT OF BOARD OF CONSULTING ENGINEERS, PANAMA CANAL.


instance, 12,000 feet you can see exactly bow many floods would be affected and how it is supremely easy to regulate the currents of the Chagres by allowing a stated amount to go through.
 Upon the central plate is shown the five serious floods that have transpired of which there are records. The lower section shows the yearly, monthly, and seasonal means of the discharge of the river at the various ruling points. The lower one is necessarily made up as a deduction from the first three, but shows the increased amount of water which is available for lockage purposes.
 On Plate X I have shown, along the course of the river, the sections of dams on the Morison principle; also dams with net heads and their relation to dams on the same principle with high heads. A similar diagram might have been made which would have displayed the great differences of volumes by the sections taken in a direction exactly opposite to that which has been used.
 I think that all of these plates make it sufficiently clear to all of the gentlemen here, and that detailed explanations are not at all necessary.
 On Plate XI I have incorporated sketch diagrams of the structure and dams at various ruling points, which have also been shown in the relief models made for the convenience of the Board. I would particularly point out that when a higher level is made between Mindi and Bohio the Gatun cut-off may be used and so diminish the distances about a mile and two-tenths nautical.
 In the lower right-hand corner you will see particularly the Pedro Miguel by-pass, which is naturally available in view of the topography at that point. The other plates do not require especial reference and I would revert to the harbor plate of Panama, VII. The relief maps which are hung in the other room show the reasons that led me to adopt a different alignment, and in this connection, with reference to the rock and earth filled dams, I want to say that with the heads that are provided I would be enabled to use hydraulic dredges, but submit that some work also should be done dry, as I have done on several occasions, so that the time of executing such dikes and low-head dams as I have indicated would be minimized.
 I think there is nothing else which the speaker cares at this time to say. There remains little that he can do, but perhaps to stand on the very spots where he would found his proposed works and state his way of executing them. I will say that if there is anything else that he can do his services are at command.
 The Chairman then stated that he desired some information concerning the east breakwater at Panama. It does not appear from Plate VII that any water would be inclosed of depth sufficient for deep-sea vessels. The west breakwater would certainly seem to prevent the sand drift which is known to exist in this part of Panama Bay. Would it not be possible to omit the east breakwater?
 Mr. BATES. I would say that it would be possible, perhaps, to do so. There is a large excess of rock to be taken from the cuttings and it seems to me that this would be a good place of deposit for it and make a highly advantageous and inclosed harbor.
 The CHAIRMAN. You look for a large growth in the city of Panama?
 Mr. BATES. I think so. For instance, I have had occasion lately to know something about the possibilities of iron and coal in northern Peru, and it would appear that there are large deposits of orc as well as oil in northern Peru. The former compares favorably with the best character of iron ore found along Lake Superior, and these and other resources might mean a very large traffic to the canal.
 Mr. RIPLEY. A statement was made that it costs from five to ten times as much for submerged-rock excavation as it does for rock excavation in the dry. I would like to ask for information concerning these prices.
 Mr. BATES. It is a matter of depth and conditions. The depth, for instance, in the Hay Lake channel is about 20 to 22 feet.


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