IMPROVEMENT OF APPARATUS.

Service tests have been made of an automatic submarine bell mechanism attached to a buoy in which a vane operating the hammer is protected by a casing, and as the buoy rises and falls on the waves the vane is forced up and down, causing a spring to stretch. At a certain point this spring is released, and a blow is struck. All blows are of equal intensity, being due to the elongation of the spring, although the interval between blows varies with the condition of the sea. The bell rings uninterruptedly and independently of the condition of the weather, and from reports received has been heard for distances of 10 to 15 miles. One such submarine bell buoy is in commission.

Steps have been taken to encourage American glass manufacturers in the production of lighthouse lenses, which have heretofore been purchased abroad. Experimental lenses have been ordered, and when completed will be given a service trial. A considerable economy in cost is expected.

Two methods for changing fixed to occulting lights have been further used at various stations, by revolving opaque screens within a fixed lens and by revolving the lens itself, certain glass panels having been removed and their places filled with screens. The screens are given the proper openings to produce the desired characteristic. By these methods it is possible to change lights heretofore fixed to occulting lights at small expense, saving the cost of new lenses. Fixed lights are often objectionable on account of the possibility of confusion with other lights on shore.

To facilitate the replacing of light vessels on exposed stations in foggy weather, whistling buoys have been introduced as marking buoys for several important light-vessel stations.

Automatic pressure and recording gauges have been installed at a number of fog-signal stations. These gauges are fitted with circular charts upon which a pen automatically indicates the exact times during which the signal is operated.

Experiments are under way with devices designed to summon light keepers by ringing an electric bell when lights are not burning properly, either too high or too low.

The use has been extended of submerged buoys in order to relieve the strain on moorings of exposed light vessels. A spherical buoy is employed, shackled to the mooring chain, thus supporting a great part of the weight, raising the chain clear of the bottom, and acting as a spring when the vessel strains at her moorings in heavy weather. An additional installation has been made of an electrically operated fog bell actuated by a mechanical tripping device from a power house on shore. A telltale electric lamp on a switchboard in the power house indicates by its light whether the bell is in operation.

Experiments are under way with a double mirror intended to increase the intensity of occulting lights and lengthen the duration of light in flashing lights.

Enameled metal signs warning persons against damaging lighthouse property have been distributed for use at stations not having resident keepers.

The use of standard padlocks for unwatched lights, isolated structures, etc., where a keeper is not constantly in attendance, has been introduced. By this system access to such structures can be had at all times by authorized persons.

A new type of cast-iron post light has been designed for use on ends of breakwaters in exposed positions in connection with unwatched lights.

A new shoal-water type, combination acetylene gas and bell buoy, with large gas capacity, has been designed. One buoy of this type has been built and given a preliminary test, and has so far proved to be satisfactory.

VESSELS.

Under date of May 10, 1912, the Attorney General rendered an opinion holding that the employment of laborers and mechanics in making repairs to Government vessels is employment upon a public work of the United States, and is therefore subject to the restrictions of the act of August 1, 1892 (27 Stat., 340), known as the "eighthour law." As many shipyards operate under a nine-hour day, some difficulty has been experienced in arranging for contracts for such work.

One new tender, the Camellia, was completed during the year and assigned to duty in the Gulf of Mexico, and one new light vessel, No. 82, was placed on station off the entrance to Buffalo Harbor, N. Y. Plans and specifications for light vessel No. 96 were prepared and proposals invited. The Bush Bluff Light Vessel was replaced at the entrance to Norfolk Harbor, and steps have been taken to improve the lighting apparatus of light vessel No. 97, which will be placed on that station during the present fiscal year. Plans are under way for the construction of light vessels No. 98, No. 99, No. 100, and No. 101, and also for the construction of four new tenders.

The tender Woodbine is under construction, and it is expected will be ready for service during the coming fiscal year, the completion having been delayed by the failure of the contractor.

Milwaukee Light Vessel No. 95 is nearly completed and will be placed on station during the present fiscal year.

On November 23, 1911, the tender Lily was wrecked by striking a snag in the Missouri River while engaged in work of establishing aids to navigation on that river. The machinery and miscellaneous articles of equipment were saved, but the hull was a total loss.

On May 20, 1912, the tender Armeria struck a submerged rock off Cape Hinchinbrook Light Station, Alaska, while delivering coal to that station, and became a total loss, with the exception of miscellaneous supplies and equipment.

LIGHTHOUSE DEPOTS.

During the fiscal year improvements were made at the General Lighthouse Depot, Tompkinsville, N. Y., by building a power house and foundry. An extension to the dock will be commenced shortly.

The wharf at Edgemoor Depot, Del., was also under reconstruction. Sites for depots at San Juan, P. R., and Ketchikan, Alaska, were reserved by Executive order.

SAVING OF LIFE AND PROPERTY.

During the fiscal year 1912 services in the saving of life and property were rendered and acts of heroism performed by employees of the Lighthouse Service on vessels or at stations on 37 occasions.

On October 24, 1911, Mrs. Ida Wilson Lewis, keeper of the Lime Rock Light Station, R. I., died at her station, aged 69 years. She resided at the station from the age of 12, and succeeded her mother (who had previously succeeded her father) as keeper in 1879. She was perhaps the most widely known lighthouse keeper in the United States, having saved at least 13 persons from drowning on different occasions, for which she was presented with medals and other tokens.

COAST AND GEODETIC SURVEY.

GEODETIC WORK.

Rapid progress was made in the work of reconnoissance for primary triangulation of the arc extending along the one hundred and fourth meridian from Denver, Colo., to the Canadian boundary. This work began May 2, 1911, and closed August 10, 1911, during which period 720 miles of reconnoissance were completed, 300 miles of which was done after June 30. In the main scheme there are 74 stations and in the supplementary scheme 23. Provision was made for the usual connection with other systems of triangulation and with the State boundaries.

Following this work, a reconnoissance was made for primary triangulation to extend from the transcontinental triangulation in Utah to the Texas-California arc of primary triangulation in the vicinity of Needles, Cal., a distance of 310 miles. Provision was made for connection with stations and monuments of existing surveys. The time occupied in this work was one month and six days.

A reconnoissance was then made for a scheme of primary triangulation to extend from the oblique arc in the vicinity of Huntsville, Ala., to Memphis, Tenn., a distance of 232 miles; after which a reconnoissance was made for a primary traverse from Memphis to Little Rock, Ark. The length of this reconnoissance is 123 miles. The reconnoissance from Huntsville to Little Rock was made between November 8, 1911, and February 29, 1912, a period of 3 months and 22 days.

The total length of reconnoissance was 965 miles.

In May, 1912, observations were begun on the primary triangulation near the one hundred and fourth meridian by two parties working from the northern and southern ends of the arc, respectively. A signal-building party preceded the observing parties.

During the year the scheme of secondary triangulation from Tacoma, by way of Grays Harbor, to Willapa Bay, Wash., was completed. The area covered has long been in need of an adequate control for surveys and maps. This chain of triangulation is 140 miles in length and all of the observing was done during the fiscal year. This was a difficult piece of work, owing to the very high timber, fog, rain, and the great amount of smoke from forest fires.

The triangulation was completed on the Neuse River, N. C., which was necessary to connect the work of the United States Engineers,

affecting navigation, with the triangulation of the Coast and Geodetic Survey.

Two parties were engaged in the revision of triangulation on the coast of Texas during a portion of the year. Several parties engaged on chart revision and hydrography also did some work of triangulation.

At the request of the General Land Office, the latitude and longitude of a point near Copper Center, Alaska, were determined by two cooperating observers. Longitudes were determined telegraphically by the same parties at stations in Fort Stevens, Oreg.; Jarilla, Boracho, Stanton, Matagorda, and Sabine, Tex.; and the astronomic latitude was determined at six stations of the Texas-California arc of the primary triangulation.

An important event of the year was the completion of a three years' campaign of gravity determinations, during which 77 stations were established in the United States. Previous to 1909, when the recent gravity work was begun, only 47 stations in this country had been occupied with the invariable pendulums. During the fiscal year 1912 gravity determinations were made at 18 stations.

The line of precise levels from El Reno, Okla., to Goffs, Cal., was completed during the year. It furnishes a second and almost independent connection between the Gulf of Mexico and the Pacific Ocean.

Excellent progress was made on the line of precise levels from Brigham, Utah, toward San Francisco, Cal. Work on this line was begun in July, 1911, and by the close of the season 302 miles of levels between Brigham, Utah, and Beowawe, Nev., had been completed. Work on this line was resumed from the San Francisco end in March, 1912, working eastward, and by the end of the year about 300 miles of leveling had been run.

The Survey has made a contribution to geodesy in the publication entitled "The Effect of Topography and Isostatic Compensation upon the Intensity of Gravity" (Special Publication No. 10), which was available for distribution in May, 1912. A preliminary report on this subject was submitted to the International Geodetic Association at its meeting in 1909. In Special Publication No. 10 the new method of making gravity reductions (in which topography and isostatic compensation are considered) is explained at length and the necessary reduction tables are given in detail. The results of this investigation supplement and agree with the results obtained from the investigations by this Survey of the deflections of the vertical, which were published as "The Figure of the Earth and Isostasy, from Measurements in the United States," and "Supplementary Investigation in 1909 of the Figure of the Earth and Isostasy."