the total expenditures to June 30, 1888, $504,929.88. The appropriations have been as follows: Act approved July 15, 1882 Act approved August 4, 1886.. Total.. Deducted therefrom the total of expenditures ($504,929.88), the balance available for completing the work at the close of the fiscal year was.. $431,273.75 160,000.00 591, 273.75 86, 343.87 In order to complete this part of the work to the extent necessary for service in connection with the increased water supply, a gate-house (combining influent and effluent) is to be built, the side slopes of reservoir in vicinity of gate-house graded and paved, and the circulating conduits built. The balance of appropriation in hand will probably be sufficient for the work above indicated. After that is done, requisite" means for fencing and for properly finishing the grounds about the reservoir should be provided, but it is not deemed expedient to submit any estimate therefor at this time. LAND. The only payment for land during the year was that of May 26, to Martha J. Coston, for $77.50, on account of land to extend aqueduct. All previous payments are given in the Annual Reports of the Chief of Engineers for 1885, 1886, and 1887. Of the sum originally appropriated ($45,000), to pay for land and water rights at the Great Falls, only $117.96 has been expended, as stated in previous reports, no expenditure having been made therefrom during the past year. The settlement of questions concerning these matters is still pending in court, in charge of the Attorney-General. The total expenditures made from this office on account of land condemnation up to June 30, 1888, is as follows: For "land to extend aqueduct". For "land for reservoir". For "water rights and land to extend dam at Great Falls" The balances of appropriations available for the above-named purposes, June 30, 1888, were as follows: For "land to extend aqueduct" For "land for reservoir". For "water rights and land to extend dam at Great Falls". MAIN CONNECTIONS. $24,930.49 814.28 44, 882.04 No work has been done on the main connections during the year. In July a small force was employed to remove the 75-inch pipe, which had been left on the grounds of the Howard University, to the site of the new reservoir, at an expense of $19.40; the only disbursement during the year. The total expended on account of main connections to June 30, 1888, were as follows: The original appropriation was $165,400, and the balance now available is $1,989.18, which will probably suffice to complete this part of the work by making proper connection with the gate-house when built. The following is an abstract of contracts for increasing the water supply of Washington, D. C., in force during the fiscal year ending June 30, 1888: For tunnel.—Beckwith & Quackenbush, of Mohawk, N. Y., contractors; date of contract, October 29, 1883; dates of supplemental contracts, October 18, 1886, December 5, 1887, and May 8, 1888. The specified time for completing work under these several contracts is November 1, 1888, but it is not deemed possible to do so within that limit of time. For reservoir. Maloney & Gleason, of Washington, D. C., contractors; date of original contract, October 30, 1883; expired June 30, 1887, and extended under supplemental articles of agreement dated July 20, 1887, to October 31, 1857. The following is a money statement for the fiscal year ending June 30, 1888: The above statement has reference only to disbursements made from this office; in addition, the sum of $611.24 was disbursed directly from the United States Treasury Department for advertising, but I have not been advised as to what specific item of appropriation such expenditure was charged. It related to the acquisition of land and water rights, and is supposed to have been charged accordingly. Deducting this amount ($611.24) from the total available June 30, 1888 ($506,286.57), leaves $505,675.33; of this amount an expenditure of the greater part of the balance applicable to the extension of the aqueduct ($342,661.19) is contemplated under existing contracts. REPORT OF LIEUTENANT C. MCD. TOWNSEND, CORPS OF ENGINEERS. MAJOR: I have the honor to submit the following report of the operations for "increasing the water supply of the city of Washington, D. C.," during the fiscal year ending June 30, 1888. The project adopted in 1882 for increasing the water supply of the city of Washington consisted in completing the dam across the Maryland Channel and the Potomac River at Great Falls, building a dam across Conn's Island and the Virginia Channel, extending the conduit from the distributing reservoir to a ravine south of the Soldiers' Home by means of a tunnel, building in this ravine a reservoir of 300,000,000 gallons capacity, and connecting it with the distributing-pipes of the city by large iron water-mains. At the close of the last fiscal year the dam at Great Falls had been completed; the water-mains had been laid, with the exception of a few lengths at the new gatehouse; and the tunnel had been "holed," and 6,110.5 linear feet had been lined with brick and rubble masonry. To complete the reservoir so that water could be introduced required about 50,000 cubic yards of excavation, 12,000 square yards of paving, the construction of a gate-house over the eastern shaft of the tunnel, and the building of a conduit from the gate-house to cause a circulation of water in the reservoir. A description of the work done will be found fully explained in preceding reports. During the fiscal year ending June 30, 1888, the excavation and paving of the reservoir has been completed, except in the gate-house recess, and no work can there be undertaken until lining in the heading from the east shaft of the tunnel has been completed and the cages employed in hoisting material have been removed. The work of lining the tunnel was continued with a small force until September 30, when operations were suspended on account of a lack of funds. As the worst rock encountered had been lined, the tunnel was allowed to fill with water, not only from motives of economy, but also to test the strength of the lining already constructed. In the general deficiency bill approved March 30, 1833, Congress appro priated $355,000 to complete the lining of the tunnel, etc., with the proviso that the work should be finished November 1, 1888. The water was then pumped out and work was resumed, but it was not until the end of May that the building of the masonry arch could be actively commenced. During the year 3,959 5 linear feet of the tunnel were lined with brick and rubble masonry, of which nearly one-third (1,186 feet) were constructed during the month of June. The total length of the tunnel lined is 10,009.5 feet. There remains to be lined 10,626.8 feet. The following table shows the location of the various lined sections of the tunnel, the numbers under the heading "Class of lining” referring to the cross-sections submitted herewith: About 2,100 feet have been en Note.-Brick-work of 4 rings was used in west heading Champlain avenue shaft between stations 815-816, 867-1050, 1390-1440. A 3-ring invert was built from 815-846. larged for lining and 379 feet of side-walls constructed. As will be seen from the above method of lining the tunnel has been materially modified from time to time. The reasons for the change from dry-stone packing to a filling of rubble masonry have been fully explained in preceding reports. In the sections in which the invert is omitted there is no danger of the rock decomposing to an extent sufficient to endanger the stability of the side-walls, and the duty of the lining is merely to hold the rock in place. Section 4 is employed in rock considered solid enough to resist the pressure of water, and is introduced as a precautionary measure to prevent any possibility of the roof caving in. If the tunnel could readily be emptied from time to time, it might have been advisable to have left these sections unlined, but the time necessary to pump out the water and make any repairs will be so long, and the discomfort to the citizens of Washington during that interval so great, that a reasonable expenditure should be made to reduce the chances of accident to a minimum. In this connection the record of the pumping out of the tunnel when work was resumed is submitted. The pumps employed were four Knowles's mining pumps, cylinders 10 inches and 6 inches, length of stroke, 12 inches, and one Cameron pump of corresponding size. Pumping commenced at Rock Creek shaft with two pumps, March 26. At the east shaft with one pump, March 28. At Foundry Branch shaft with one pump, March 29. At Champlain avenue shaft with one pump, April 6. Foundry Branch shaft was cleared of water April 13; Rock Creek shaft, April 22; Champlain avenue, May 3; east shaft, May 16. The extra pump at Rock Creek was transferred to the east shaft when the water in the former shaft had been reduced to a depth of 6 feet. The tunnel filled with water until it flowed out at Rock Creek in about one and one-half months. The work will be vigorously prosecuted during the next fiscal year, but as it will not be completed on the 1st of November, as directed by act of Congress, it seems proper to explain fully the reasons therefor. In previous years the course had been adopted of lining those sections of the tunnel in which the rock was bad, with the intention of leaving a large portion unlined, and the lining was therefore very irregularly distributed in the different headings. Thus in the west headings, from Champlain avenue and the east shafts, the work was nearly completed, while in the east heading from Foundry Branch no masonry had been laid. In the bill approved March 30, 1888, the lining of the entire tunnel is authorized. The time necessary to complete the work now becomes a function of the rate of progress in the longest unlined heading. The operations of breaking down the rock to enlarge the tunnel for lining, and of laying the brick and rubble masonry, can be carried on simultaneously at many points, so that the rate of progress is limited only by the removal of the blasted rock and the introduction of brick and cement. By the substitution of rubble side-walls for brick, the work of hauling the material is expedited, as less stone is removed from the tunnel and less brick brought into it. Only a small force, however, can be used in loading the rock in cars, due to the small width of the tunnel, and it is found that, working continuously, the muck can be removed at a rate of but 20 feet per day when near the shaft. After the tunnel is lined the bottom must be cleaned and the tracks removed; the timbering in the working shafts must then be taken out and the shafts filled up. To complete the work in the time specified is therefore an impossibility. The attention of Congress should be called to this subject, as the proviso would appear to make the expenditure of the funds appropriated unlawful if the work is not completed at the time specified. Very respectfully, your obedient servant, Maj. G. J. LYDECKER, Corps of Engineers, U. S. A. C. McD. TOWNSEND. Y Y 3. ERECTION OF FISH-WAYS AT GREAT FALLS OF THE POTOMAC. No work has been in progress on the fish-ways during the past fiscal year, the balance of appropriation ($5,634.82) being insufficient for any useful work. Congress has, however, at its recent session appropriated $25,000 for their completion, and the United States Commissioner of Fisheries, after having caused certain preliminary surveys to be made during the months |