On October 1, 1914, a building division was organized, charged with the construction of all buildings belonging to The Panama Canal, the Panama Railroad Company, and the Army.

The force for the operation and maintenance of the canal was organized from the construction forces as far as practicable and placed in charge of the maintenance and operation of the locks.

CONSTRUCTION.

The department of operation and maintenance continued in charge of the Governor, who was assisted in the administration of the department by the engineer of maintenance and the marine superintendent. In compliance with orders, Col. (now Brig. Gen.) H. F. Hodges, United States Army, was relieved from duty as engineer of maintenance on January 1, 1915, and Lieut. Col. Chester Harding, United States Army, was assigned to this duty. The designation "Superintendent of transportation" was changed to "Marine superintendent" as more suitably designating the duties of the position, and Capt. Hugh Rodman, United States Navy, continued on this duty.

The engineer of maintenance was in charge of the completion of the locks, the electrical and municipal divisions, meteorology and hydrography, general surveys, the office engineer, and the operation and maintenance of locks.

Locks. The lock-operating machinery was practically completed during the preceding fiscal year; the principal exception was the installation of the chain fender machines, which was still in progress, and these machines were completed, so far as concerns the mechanical installation at Gatun on November 30, 1914, and at Pedro Miguel and Miraflores on September 4, 1914. The electrical installation was completed at these three localities on November 30, 1914, October 28, 1914, and June 25, 1915, respectively. Delay was occasioned by a change in plans by which the motors above the sump pumps were raised, thereby increasing considerably the capacity of the sumps and requiring the pumps to operate less frequently. The delivery of the chains was completed on January 6, 1915, and they are all installed.

The telephone systems on all the locks were completed in February, 1915; a description of the system adopted was given in the annual report for 1914.

Delivery of the towing locomotives under order from the General Electric Co. was completed on November 14, 1914. They have operated very successfully, and, in accordance with the specifications, at a speed of 2 miles per hour. This speed is too high for vessels of heavy tonnage, so that experiment was made to determine the effect of connecting two traction motors of each locomotive in cascade,

suggested by Mr. R. H. Whitehead. This reduced the speed to 1 mile an hour and was so successful that material has been ordered to permit changing all the locomotives which will then have speeds of 1 and 2 miles per hour, the change from one to the other being accomplished by throwing a switch in the cab, within easy reach of the operator.

The back fill of all the locks was placed prior to the beginning of the fiscal year, but as it was left in very irregular shape the back fill of all the locks was graded and sloped, with the view to improving the general conditions and appearance around the locks. At Gatun the work was placed under Mr. John J. Walsh, general foreman, who was in charge of the work of leveling off, grading, and sodding the slopes of Gatun Dam. On the Pacific side the work was under the superintendent of the locks. Due to the advent of the rainy season, the work at Miraflores was not completed. The amounts expended were $32,742.32 at Gatun, $20,631.20 at Pedro Miguel, and $19,207.87 at Miraflores.

The temporary wooden structures at the various locks, which housed machinery for local repairs during construction, were unsightly and dilapidated. As such machinery is necessary at the lock sites for minor repairs in connection with the maintenance of the lock operating machinery, permanent repair shops were erected to take their places, one each at Gatun, Pedro Miguel, and Miraflores. They are reinforced concrete buildings, 110 feet long and 38 feet 6 inches wide, and contain dry rooms, open and closed storage spaces, blacksmith shop, general shop, and latrines for white and colored employees.

The floating caisson was completed and arrived at the canal on October 29, 1914, was tested at Miraflores locks, accepted, and used during the year to permit the painting of the gates of the Pacific locks. Electrical division.-This division continued in charge of Capt. William H. Rose, United States Army. The hydroelectric station at Gatun, having been tested out, was put in service on July 13, 1914, and since then has been in continuous operation. The average production cost of current during the last six months of the fiscal year was .09 cents per kilowatt hour, and the average cost delivered from all substations was .65 cents per kilowatt hour. These costs do not include the charge for functional depreciation of 3 per cent of the capital cost of the entire power system. Including this, the costs. were .44 and .99 cents per kilowatt hour, respectively.

When the hydroelectric station was put in service, the Gatun steam plant was shut down and since then has not been operated for the generation of power. The Empire steam plant, together with the compressors at this locality, was shut down permanently on September 17, 1914, and the Balboa plant on May 23, 1915. The Balboa

air-compressor plant continued to operate during the year supplying air to the Balboa shops and the terminal construction work.

The construction of the Gatun substation was so far advanced that part of the equipment was placed in service in October, 1914. Both Gatun and Cristobal stations were placed in complete service on December 5, 1914, and the Balboa and Miraflores substations on December 3, 1914.

Construction work in connection with the transmission line was completed during the year, and the sections between Gatun and Cristobal, and between Miraflores and Balboa, were placed in operation on December 3. The section between Gatun and Miraflores was placed in service on January 2, 1915, by which time the overhead telephone and telegraph wires of the Panama Railroad system had been installed in the new duct lines.

When the transmission line was put in service the Miraflores steam station was operated as a reserve plant, several of the boilers being kept under pressure at all times, so as to provide prompt resumption of service in case of failure on the part of the transmission line.

A substation was constructed at Gamboa for the new pumping plant of the municipal division, the sand and gravel handling plant of the Panama Railroad Company, and for local lighting. It was placed in service during February, 1915, and contains two transformers of 666 KVA capacity each, with the necessary oil switches, lightning arresters, etc. A substation was also constructed and placed in operation in March, 1915, for the Darien High Power Naval Radio Station. It contains two 266 KVA transformers and auxiliaries. This work was paid for by the Navy Department.

A large amount of construction work was done in connection with the installation of underground conduit systems for the distribution of electric light and power, and for telephone, telegraph, and firealarm service in the permanent towns, for the supply of the coaling plants, dry docks, pumping station, and for the Army posts. Street lighting is being installed in the permanent towns of Ancon, Balboa, Pedro Miguel, Gatun, and Cristobal, and was carried to about 90 per cent of completion during the fiscal year. The lights are of the new gas-filled, tungsten flament type, 6.6 amperes, 150 candlepower rating, and are inclosed in 14-inch polycased globes, mounted on top of ornamental cast-iron posts. The spacing varies from 150 to 220 feet, dependent on local conditions. The mounting height is 10 feet 3 inches to the center of the globe. There are 367 lights in the Ancon-Balboa district, 22 at Pedro Miguel, 57 at Gatun, and 74 at Cristobal.

The light and power installations in the Balboa shops were completed, and the Mount Hope dry-dock shops were electrified and a

2,500-cubic-foot motor-driven air compressor installed. Two 550kilowatt rotary converters were installed, one each at Gamboa and Balboa dock. Three installations of large motor-driven relay pumps were made for the dredging division, and the floating pump barge was equipped for service at the locks.

Work was done for the Navy Department in the electrical installation of three radio stations. In the construction of quarters and other buildings for The Panama Canal and for the Army and Navy Departments considerable work devolved upon the electrical division. The decision concerning size and number of generating units to provide power for the canal was determined in May, 1911, and was based on studies made prior to that date of the probable power demands that would be required. The result of the studies showed a probable day load of about 4,000 kilowatts, assuming that the Panama Railroad was not electrified, but if this were done the probable day load was computed at approximately 5,000 kilowatts, with one hour's peak of 5,700 kilowatts. This assumption was also based on the fact that electric current would be generally used for domestic purposes. Under these circumstances the generating equipment installed, furnishing 6,000 kilowatts, allowed for a reserve for future growth of about 1,000 kilowatts. In August, 1912, Congress authorized the construction of coaling stations, dry docks, and machine shops, and, though estimates for the probable amount of power that would be required for these purposes were prepared and considered in determining the power plant, the completed designs show power requirements greater than the estimates. Additional demands are made upon the power by reason of the United States Navy submarines stationed in the Canal Zone; by the light and power loads at Forts Randolph, Sherman, and Grant; and by the new waterworks for the south end of the canal, designed and undertaken since the original studies. The result is that the time is not far distant when additional power will be required, and provision should be made for increasing the capacity of the existing plant and installing a reserve unit. Estimates to be submitted for the latter will include the duplication of the present power house and the installation of one additional unit. Anticipating that an extension might become necessary with time, the penstocks and tailraces were provided in the construction of the spillway during the construction period.

Municipal engineering.—The division of municipal engineering was in charge of Mr. George M. Wells, as resident engineer, until May 10, when, due to the practical completion of the Panama waterworks, he was assigned to other duties and the work of the division was transferred to Mr. D. E. Wright, as municipal engineer. The division is divided into two districts, the northern district covering that part

of the Canal Zone lying north of Darien, including the city of Colon, and the southern district embracing the Canal Zone lying south of Darien, including the city of Panama.

The work on the Panama waterworks, which was undertaken during the previous fiscal year, was completed. As previously reported, the original plan contemplated the location of a pump station at Miraflores, utilizing the waters of the lake as the supply; but this had to be abandoned, due to the heavy rise in chlorine in the Miraflores Lake. This pump station, which was nearly completed when the source of supply had to be changed, was remodeled and transferred to the fortification division for use as a storehouse. A station was then built at Gamboa, and the pipe line, extending from Gamboa to Miraflores, was installed during the year. It required the laying of 59,762 linear feet of cast-iron pipe, varying in size from 24 inches to 36 inches in diameter. The trench was excavated by contract at a total cost of $22,000, and the total cost of the pipe line, including the cost of pipe, fittings, excavation, and backfill, was $356,951.10.

The construction of the Miraflores purification plant was about 45 per cent completed on June 30, 1914. The plant was completed and put in operation on March 16, 1915. It consists of the wash-water tank, the aeration basin, the head house, the sedimentation basin, the filter building and pipe gallery, the laboratory and quarters, the clear-water basin, and the injection chamber. The total cost of the plant was $558,168.41, of which $203,625.12 was for work done during the year. Walks and a roadway were constructed around the plant and the latter connected with the Canal Zone road to Panama.

The delivery of water from the purification plant at Miraflores to the pump station at Balboa is through three parallel lines, each 21,000 feet in length, the diameters being 30 inches, 20 inches, and 16 inches, respectively; this work was also completed during the fiscal year.

As part of the new waterworks, an extension was made to the existing high-service reservoir on Ancon Hill, at elevation 300, by constructing an addition having a capacity of 1,500,000 gallons. This work was practically completed at the close of the last fiscal year.

Three pump stations, one at Gamboa, one at Miraflores, and one at Balboa, were constructed, together with the necessary grading and paving and the installation of the machinery and fittings, at a total cost of $200,654.22. The total cost of the new Panama waterworks was $1,387,490.57.

In addition to the new water-supply system, work was in progress during the year on the construction of roads and walks, water and sewer systems, and the grading and sodding of grounds in the Balboa townsite. This work was under the landscape architect from