REPORT OF BOARD OF CONSULTING ENGINEERS, PANAMA CANAL.


under full headway the average per cubic yard should be reduced to a small amount on the cost per cubic yard of the output.
 In the writer's opinion, throughout the conduct of the work this expense should not exceed
3 cents per cubic yard.
 It is again called to the attention of the Board that the costs contained in this statement were obtained by experimental work under the most disadvantageous circumstances, with crude machinery and an ill-assorted force of inexperienced men, but that an endeavor was made to handle the classes of material in approximately the assumed proportion which would exist throughout the work, and that the probable unit prices suggested were arrived at not only after a careful study of actual conditions on the ground during a year's experience, but also in view of the writer's experience in other work of a similar nature carried on under his supervision in the United States, and also considering the economies which can be effected by the installation and adoption of proper machinery, appliances, methods, and supervision.
 The total of the various units suggested by the writer aggregates 48 cents per cubic yard, including arbitraries. While he feels that efficient supervision, such as a contractor would give to this work, might very materially reduce some of the items of cost enumerated herein, he suggests in the consideration of the question that 50 cents per cubic yard, in round figures, would be an ample unit cost for the entire work, which, however, for greater safety, might be increased 20 per cent, which would be considered the profits of a contractor during the work, bringing the estimated cost up to 60 cents per cubic yard.
 With reference to the distribution or figuring items of cost, while the suggestion might be made that theoretically mining should be considered part of the excavating and transportation part of the dumping branches, it should be borne in mind that this distribution of costs, devised and instituted by the writer, was intended *to so subdivide the work as to enable the chief engineer to properly measure the efficiency of men and appliances. For instance, the superintendent in charge of mining and the men under him should be measured by the cost of mining alone. In the excavating and loading department, the efficiency of the superintendent of steam shovels and the men operating them would naturally be measured by the cost per cubic yard of the actual steam-shovel work, as account can be kept of each steam shovel separately and the measure of efficiency ultimately applied to each individual excavating machine.
 In the maintenance of tracks, the various supervisors and foremen in charge of different sections of track work can be measured by the number of miles of track each had to maintain, but as it is affected by the tonnage passing over the same, the cost per cubic yard, which is the measure of use made of the tracks, should be considered.
 Under the head of transportation is all the expense that is due to the moving of cars froni the time 'he loaded car is taken from the shovels until the empty car is returned thereto; and the cost per cubic yard moved some distance, say 1 mile, will naturally be the measure of efficiency applied to employees of this department. This record can be kept for each train crew or each set of crews, and again each division of the work can be segregated and its efficiency measured thereby.
 On the dumps, where a foreman with a gang of men is stationed, whose function it is to render such assistance as may be necessary in addition to train-crew work, unloading cars and maintaining tracks actually on the dumps and spreading the material, the cost per cubic yard of the material dumped is, with proper consideration being given to other conditions, a fair measure of the efficiency.
 This unit of efficiency can also be applied in comparing the cost of various dumps and determining whether it is more economical to form a high dump with only occasional movement of tracks but with excessive bank settlement, or to spread the material for a low dump over a larger area with more frequent movement of tracks.,
 While it is doubtless true that the cost of one part of the work is affected by others with which coordinate work is carried along, still the writer has found in his experience that a careful record of cost units, changing and modifying the system as necessary from time to time, with proper analysis, not only gives the person in responsible charge. of the entire work a knowledge and control which he could not possibly obtain from simply general observation, although close


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