United States against deterioration, whether from bridging or other causes; upon the geodetic and hydrographic survey of the lakes; upou surveys for the defenses of the coasts; upon military surveys and recounoissances in the interior; upon geographical and geological explorations; upon pubiic buildings and grounds in the District of Columbia; upon the construction of light-houses, and upon the demarkation of the boundary between the United States and Great Britain.

The works projected and approved for the modification and strengthening of our sea-coast defenses and fortifications have been advanced with a rapidity consistent with economy and efficiency, and the works for our principal harbors now contain quite a number of platforms ready for their armaments of guns of the largest calibers. Heavy guns mounted in covered positions, along the shores of the inlets to our harbors, must always be the basis of any successful defense, and the works projected and in course of construction should be prosecuted to completion, and be suitably armed.

The Battalion of Engineers numbers 308 enlisted men, and is stationed at the Military Academy for instruction of cadets, and at Willet's Point, New York Harbor, where it forms the school of torpedo defense of the channels to our harbors, and the guards and workmen for the care and distribution of engineer-equipments. During the past summer a num ber of detachments have served with advantage in the geographical and geodetic explorations. The appropriations asked for the engineer depot and post are recommended to Congress, and the recommendation for one chief musician and two principal musicians for the battalion approved.

With the small appropriations granted for trials with torpedoes, the investigations upon this subject have been continued, to the benefit of our system of submarine mines. This accessory for the defense of our harbors in recent years has developed into one of great importance among the maritime powers, and to investigate the recent electrical methods and systems of torpedoes, as well as to procure certain materials, two officers of engineers were sent during the summer to Europe. The results of their mission are the collection of valuable information on this subject, and a saving of expenditure to the Government.

The river and harbor improvements mentioned in my last annual report have been continued, and the works and surveys connected therewith have been carried on during the past year with vigor. Detailed information in regard to each specific improvement, and the results of surveys directed to be made by the river and harbor appropriation acts, may be found in the report of the Chief of Engineers.

The improvement of our rivers and harbors consists, chiefly, in giving increased width and depth to existing channel-ways and basins, and protecting thein, or in creating new channels and basins and giving them protective works. The operations to this end comprise the removal of obstructions of various kinds, such as rock in place and bowlders,

bars of clay, sometimes indurated; of gravel, sand, and other alluvial matter; of rafts, often extending from the surface of the river nearly to the bottom, formed by masses of drifting trees, or the accumulation of slabs, edgings, and sawdust; of timber and other constructions placed in channel-ways to obstruct or close them; the construction of dikes, dams, wing-dams, and revetments, and the building of canals, breakwaters, and piers, all tending to promote the general interests of commerce and navigation, by furnishing increased facilities of communication and giving greater security to trade.

The condition of the public works and grounds of Washington, and the progress made in their construction, repair, and improvement, are very creditable to the officer in charge. The improvements exhibit good taste, with much economy of expenditure. Many vacant and unimproved reservations have become attractive places of puolic resort, at little expense.

In accordance with the proviso attached to the appropriation for the improvement of the channel of the Delaware River at or near the Horseshoe Shoals, a board of engineers was convened; and in view of their report upon the feasibility and expense of the plan proposed for the prevention and removal of the obstruction, it has been determined to defer final action upon the proposed plan until after the method adopted by the local authorities is fully tested, and it is found that the means used by them will not be sufficient to maintain an open channel during the winter months.

Section 3 of the river and harbor act of March 3, 1873, directed that a report be made upon the practicability of bridging the channel between Lake Huron and Lake Erie, without material injury to the interests of navigation, and upon the number and character of vessels navigating that channel. The subject has been committed to a board of experienced engineer officers, who are now engaged upon it. It is expected that their report will be received during the early part of the session of Congress.

The removal of the wreck in the channel-way off Sandy Hook, required by the act approved January 3, 1873, was completed March 6, leaving a clear depth of 25 feet at mean low water.

Under the authority granted by the act approved January 23, 1873, a contract was closed for the construction of an iron hull for a lightdraught snag-boat for use on the Mississippi, Missouri, and Arkansas Rivers, and it is expected that the boat will be ready for service during the present season.

The Lake Ontario Shore Railroad Company submitted a project for a bridge across the Genesee River, and in accordance with the provisions of the second section of the act authorizing its construction approved March 3, 1873, certain modifications in the plan were required, and of these the president of the railroad company has been notified.

In carrying out the provisions of recent acts of Congress authorizing

the construction of bridges, my attention has been called to the fact that certain bridges have been built, and that one is now being constructed across navigable waters of the United States without any authority of law; and further, that certain parties claim the right to bridge, and that one of those parties is now constructing a bridge under authority claimed to be derived from acts granting right of way for railroads through public lands and granting lands to aid in the construction of a road chartered by State authority. In view of the provisions of the more recent acts of Congress requiring the Secretary of War to maintain a supervision over the location and construction of bridges crossing navigable waters of the United States, in order that the interests of navigation shall be protected, I feel it my duty to invite the attention of Congress to this subject and to suggest such general legislation as may be deemed necessary for the preservation of the great natural channels of commerce.

In this connection I have respectfully to recommend that the act authorizing the construction of a bridge across the Arkansas River at Little Rock, Arkansas, approved May 31, 1872, be repealed, for the reason that a bridge constructed in compliance with its terms would materially obstruct and impair the navigation of the river. A previous act of Congress (that of July 1, 1870) contains all the provisions for bridg ing this river at Little Rock essential to the preservation of the channel. The survey of the lakes has been continued with success during the season. The survey of Lake Michigan has been pushed forward nearly to completion, and that of the Saint Lawrence River has been extended nearly to Lake Ontario. Other portions of the survey are in satisfactory progress; new surveys of special localities have been made, the longitude of important points determined by telegraph; assistance to the geographical and geological survey of adjacent States rendered; and meteorological and lake-surface observations continued through the entire lake region.

The main field operations of the geological exploration near the fortieth parallel, between the Sierra Nevada and eastern slope of the Rocky Mountains, were completed in November last, and the maps and results are being prepared for publication at an early day. Special examinations, giving important results, have been made of noted geological structures, and of the evidences of glacial action in the Sierras.

The geographical and geological surveys and explorations west of the one-hundredth meridian in Nevada, Utah, Colorado, New Mexico, and Arizona, have been prosecuted with great vigor and success. The field labors terminated in December, after which the work of preparation of the maps and observations for publication was continued in the office in this city. The field operations of the present season, embracing, in addition to the usual observations in the various branches of the survey, the erection of a field astronomical observatory at Ogden, Utah, and the

determination of an astronomical base, commenced June 1, with an efficient organization.

The officers of the Corps of Engineers on detached duty at the headquarters of general officers commanding military divisions and departments have rendered valuable services in preparing such maps and sketches and making such surveys and reconnaissances as were required by their commanding officers. Besides these regular duties, several special reconnaissances have been made, yielding important information Among these the reconnaissance of the lava-beds and surrounding country, the scene of operations against the Modoc Indians; the survey of the Yellowstone River, as far up as practicable; the reconnaissance of the head-waters of the Rio Grande and Southwestern Colorado; and the reconnaissance to discover an approach to the Yellowstone Lake Basin from the south or southeast, thus opening a new and shorter route to the National Yellowstone Park and the mining regions of Montana, together with the results of astronomical observations to determine the positions of important points, are particularly referred to in the report of the Chief of Engineers.

The commission appointed by the President, in accordance with the act approved March 3, 1873, to examine and report on a system of irrigation in the San Joaquin, Tulare, and Sacramento Valleys, California, met and organized in San Francisco in May, and proceeded at once to examine the valleys in question and the streams emptying into them. By the end of June they had made satisfactory progress. They are still engaged in this labor, and in the collection of information to enable them to render a full report upon the subject of investigation.

A complete set of the published maps and reports of the Engineer Department, together with sets of photographic views of remarkable natural features of the western country, and models of important engineer work of river and harbor improvement, and of armament, were prepared and forwarded through the commissioner appointed by the President to represent the United States at the Vienna Exhibition, with authority to present them, at the close of the exhibition, to the engineer department of the Austrian army.

The estimates of the Chief of Engineers are submitted separately, as presented by that officer, viz:

Fortifications and other works of defense....

Public buildings and grounds and Washington aqueduct...

Surveys.....

Engineer depot at Willet's Point, N. Y.

Office expenses....

$3,376,000

1, 118, 056 420,000 20,800 29, 260

Improvement of rivers and harbors......

15, 464, 540

Total

20,488, 656

No steps have been taken by me to carry out the provisions of the act of March 3, 1873, authorizing the survey, plat, and sale of the cem etery grounds upon the Fort Gratiot military reservation in Michigan,

as the formal preliminary action of the city authorities of Port Huron has not yet been completed.

The report of the Chief of Ordnance calls attention to the many potent arguments so often presented in favor of the repeal of the law prohibiting promotions in the corps which he represents. He refers to the hardship and humiliation to which officers of merit and long service have been subjected since the passage of that law, by being deprived of their deserved promotion, the only reward held out in their profession for years of duty well performed. Their claims to promotion appeal strongly to the attention of Congress.

A board of experienced officers, of which Gen. A. H. Terry was president, was convened in September, 1872, for the selection of a breech-loading system for the muskets and carbines of the military service. After an exhaustive trial of all the systems presented, the board selected the Springfield breech-loading system as the one, of all those brought before it, which is best calculated to meet the demands of our military service.

The report of the board was approved, and the Springfield system of breech-loader will henceforth be used for the muskets and carbines of the Army. At the same time the caliber of all small-arms for the service-rifles, carbines, and revolvers has been fixed at .45 of an inch. It is now a question of grave importance whether new arms of the accepted system shall not be made at once in sufficient quantities for a reserve supply in case of war, and to this end an appropriation of $500,000 has been asked for the next fiscal year for the manufacture, together with the materials now on hand, of about 35,000 arms.

The annual appropriation of $200,000 for arming and equipping the militia, an amount tixed by Congress during the early part of the century, is now found inadequate, by reason of the great increase of popu lation, to supply the wants of the whole body of the militia, and it is therefore recommended that the appropriation for that purpose be increased in a manner proportioned to the increase of the population since the passage of the act of 1808, providing for the distribution of arms to the militia of the country.

I feel great hesitation in recommending increased appropriations at this time, but I deem it my duty to say that the armament of our seacoast defenses, which involves the question of the defense of our principal sea-board cities from attack, in case of war with a naval power, is a subject demanding the earnest attention of Congress. The principal cities on our coast are in a very defenseless state, and the tedious and costly work of preparation caLLot be commenced on the breaking out of a war, with the hope of accomplishing any adequate result. The work must be done in time of peace, without waiting for an uncertain period in search after perfection in gan-constructions. The importance of this subject increases with the earnest and continued efforts on the part of all nations to supply their forts with the most improved armament, and