OFFICE OF THE CHIEF OF ENGINEERS, Washington, D. C., October 21, 1876. SIR: I have the honor to present for your information the following report, upon the duties and operations in the Engineer Department, during the fiscal year ending June 30, 1876: OFFICERS OF THE CORPS OF ENGINEERS. The number of officers holding commissions in the Corps of Engineers, United States Army, at the end of the fiscal year, was 107 on the active-list, and 5 on the retired-list; the latter, however, under the law of January 21, 1870, not being available for duty. In the duties devolving upon the corps by law, and its organization, the employment of a number of scientists and assistant engineers has been necessary. The only change in the officers of the corps since my last report, is the resignation of Capt. Asa H. Holgate, December 9, 1875. On the 30th of June, 1876, the officers were distributed as follows: On duty, office of the Chief of Engineers, including chief. On duty, projection and construction of fortifications.. On duty, construction of fortifications and light-house duty. On duty, construction of fortifications, and river and harbor works, and surveys for same... On duty, construction of fortifications and river and harbor works and light-house duty, and surveys for same... a harbor works, and surveys for same..... On duty, construction of river and harbor works and light-house duty, and surveys for same.... On duty, survey of northern and northwestern lakes.. On duty with battalion of engineers.... meridian On duty, public buildings and grounds, District of Columbia. On duty under Board of United States Executive Departments, collecting and arranging articles pertaining to Engineer Department for the International Exhibition, 1876.... On sick-leave Detached on duty with the Secretary of War, the General of the Army, generals commanding divisions and departments, light-house establishment, Military Academy, survey of northern boundary-line under Department of State, and the Board of Commissioners of the District of Columbia... Awaiting orders...... Total 18 4 15 5 7 14 2 1 23 1 107 The officers detached were on duty as follows: Col. I. C. Woodruff, engineer third light-house district..... Lieut. Col. William F. Raynolds, engineer fourth light-house district. Maj. F. Harwood, engineer fifth light-house district Maj. P. C. Hains, engineer-secretary to the Light-House Board.. 1 Maj. G. L. Gillespie, on staff of Lieutenant-General commanding Military Division of the Missouri.. Capt. William A. Jones, engineer sixth light-house district.. Capt. William S. Stanton, on staff of commanding general Department of Platte.. First Lieut. E. H. Ruffner, on staff of commanding general Department of the Missouri First Lieut. J. C. Mallery, on staff of major-general commanding Military Division of the Pacific... First Lieut. Edward Maguire, on staff of commanding general Department of Dakota First Lieut. R. L. Hoxie, chief engineer of the District of Columbia, under the direction of the board of Commissioners..... First Lieut. F. V. Greene, on duty in the office of the Secretary of War Capts. William J. Twining and J. F. Gregory, on duty under Department of State, upon joint commission for the survey of the boundary-line along the forty-ninth parallel Capts. C. W. Raymond, A. M. Miller, T. H. Handbury; First. Lieuts. J. G. D. Knight, S. E. Tillman, C. F. Palfrey, and William H. Bixby, on duty at the Military Academy... Total 1 1 1 1 1 1 1 23 The following principal geologist and civil engineer were employed on the 30th of June: Clarence King, geologist, in charge of geological exploration of the fortieth parallel; and S. Thayer Abert, in charge of river and harbor improvements on Potomac River and Chesapeake Bay. SEA-COAST AND LAKE-FRONTIER DEFENSES. During the past year the work upon our sea-coast defenses has progressed as rapidly as good workmanship and the amount of the appropriations granted would permit. The close of the late civil war found the naval armaments of maritime nations provided with new and powerful devices, which they had not possessed prior to the experiences of that conflict. Iron-plated ships, invulnerable to shells, propelled by powerful engines, armed with rifled ordnance of large calibers, and capable of navigating the ocean, were the outgrowth of the period of our late civil war. The sea-coast works of that day, for defense against and resistance to naval armaments, had been proportioned and constructed for armaments of much less weight and power than those now in existence-and the safety of our commercial cities, navy-yards, and war depots required that the sea-coast defenses existing in 1865-'66 should be materially strengthened by the enlargement in some cases of their parts, the addition of other works, the adoption of some new appliances, and the introduction of heavier armaments. After a careful study of the subject by the Corps of Engineers, and with the light afforded by the experience of actual conflict between seacoast defenses and the new naval armaments, the system to govern the future construction of our works was elaborated in 1869, and will be found stated in detail in Executive Document No. 271, House of Representatives, Forty-first Congress, second session, where it will be seen the system received the approval of the General of the Army and the Secretary of War, and since then has been repeatedly endorsed by the action of Congress. The main features of this system are the use of heavy earthen barbette batteries, with parados and traverses, of heavy mortar-batteries, and of obstructions in the channels, (mainly electrical torpedoes,) to hold vessels from running past the batteries and reaching the cities or depots beyond them. Works of this character have been steadily progressing since 1869, and in many of our harbors are well advanced towards completion, but in none of the harbors are these alterations finished, while in some of our important harbors along the Gulf-coast the works are scarcely commenced. Regarding the pressing necessity for the completion of the works in advance of hostilities, I beg leave to quote from my remarks of last winter to the Military Committee of the House of Representatives, contained in report No. 354, House of Representatives, Forty-fourth Congress, first session, pages 179 and 180: In the event of war with a maritime nation, if we had no well-digested system of seacoast defense ready for use, the cruisers and war-vessels of the enemy could run into our harbors, and without landing could either destroy the property along the shores or else lay the people under contribution. The accurate detailed charts of our harbors and channels, published by the United States Coast Survey, are accessible to all such nations, and are doubtless in their possession. If the enemy possesses depots and arsenals in close proximity to our shores, the arrival of such armed vessels will follow in a few hours after the declaration of war. Thirty-six hours' steaming could bring vessels from Halifax; six bours, vessels from Havana, and ninety-six hours, vessels from Victoria, Vancouver's Island, to important harbors of the United States. There might be very little time for preparation to meet the assaults of iron-plated ships, for they are plated with from 6 to 15 inches of iron, and carry rifled guns from 9 inches to 14 inches bore, all of which guns are more powerful than any gun we have in our service. With a fleet or even a single vessel of this kind in one of our harbors it would be of no avail to collect troops in the city or town threatened. Suppose with our railroad facilities we could concentrate 100,000 men in twenty-four hours at the point threatened, of what use would they be against the armored ship? Suppose that in a night the men concentrated could throw up earthworks and mount 32-pounders, 42-pounders, 100-pounder rifles, (even if it were possible to handle guns of this small size with the rapidity assumed,) what injury could all this do to the armored ship in question? The projectiles from such batteries would fall harmlessly from the side of the enemy. While lying, if need be, beyond the range, even, of our guns, with his more powerful armaments he would pierce such parapets through and through, dismount the guns, and explode such magazines. But it may be said that we would mount guns as powerful and even more powerful thau those of the enemy. Doubtless this would be done, first, if we had such guns in our service, and, second, if we had the time. over 25 tons. > Our largest gün, of which we have any number, is a 15-inch smooth-bore, and weighs We have about 325 of them for our entire coasts of 12,600 miles, exclusive of Alaska, and beyond a range of 1,200 yards it is a less powerful gun than the 9inch rifle of 12 tons. The 10-inch rifle weighs 18 tons, the 11-inch 25 tons, the 12-inch 35 tons, and the 14-inch 81 tons, and these guns are immeasurably superior to our 15inch smooth-bore. They are the kinds of guns we must mount in batteries against the iron-plated vessels. But their great weight and size require corresponding dimensions in the batteries in which they are placed and in the strength and solidity of the platforms upon which they are mounted. The parapets and traverses of earth and sand to protect them must be three and even four times as thick and massive as they were formerly built to resist the armaments of fifteen years ago. Where the parapets of earth were but 10 feet in thickness, now they must be 40 feet. Guns that were formerly dragged with ease by fifteen or twenty men and placed in position over night are now supplanted by armaments of such huge masses that special mechanical appliances are required to move them even slowly, and cannot be lifted upon their supports without the aid of hydraulic power. No matter how many men may be at our disposal, the time required to place the modern armaments in position is vastly greater than for the guns of fifteen years ago; and before such works could be improvised in a harbor the enemy in his iron-clads will have accomplished all he desired and have sailed or steamed for some other harbor to repeat the injuries of the first. But suppose the harbor in question was on the New England coast, and the season of the year the winter, when the ground is frozen hard, then the erection of efficient earthen batteries would be out of the question; or suppose the harbor was on the Gulf-coast, and the season the fall of the year, when only the acclimated could resist the effects of the malarial shores, under such circumstances the erection of efficient batteries would be exceedingly difficult. Our country is contiguous throughout its northern boundary with the most powerful maritime power of the earth, and close upon our southern shores is another, whose strength is not to be despised. These are the nations with whom complications are most likely to arise. Many of our works are in an unfinished, transition state; our supplies of torpedo materials are insufficient; the caliber and force of our guns are too small, and under these circumstances I must reiterate, the work on our sea-coast fortifications should not be suspended. Repeating these views, and impressed by the importance of the subject, involving, as it does, such great national interests, I again urge the preparation of our harbors for successful resistance against the incursions of the powerful iron-clads of the present day. For detailed report upon the several works of fortification, I beg leave to refer to the synopsis of reports of the several officers in charge. The estimates for the works have been carefully revised by me and are earnestly recommended. Special attention is asked to the estimate of $150,000 for torpedoes. This most valuable invention of modern warfare is used to form an obstruction and obstacle to the entrance of our harbors, and to hold the enemy's vessels under the fire of the shore batteries. The charges in the torpedoes are fired by the electric current, and many parts of the system cannot be obtained in an emergency. It is to procure and store such portions of the apparatus as cannot be speedily obtained in the event of sudden hostilities that the appropriation is asked. FORTIFICATIONS. Fort Wayne, Michigan, in charge of Lieut. Col. C. E. Blunt, Corps of Engineers.-This work commands the channel of Detroit River, and with its exterior barbette batteries already planned, will control the navigation of that stream. The brick scarps of this work need extensive pointing and repairs, the latter made necessary by insufficient drainage. These matters have not been taken in hand for want of funds, nor can they be this season for the same reasor. The rebuilding of the fences around the reservation, and the regrading of the grounds along a part of the boundary-line, were reported last year as half finished and in progress. This work was completed in August, 1875, at a cost of $2,011.28 allotted from the appropriation for contingencies of fortifications. No preparations have been made or are intended for any change in the armament of the work. No appropriation was made for the fiscal year ending June 30, 1877. Fort Porter, Black Rock, near Buffalo, N. Y., in charge of Lieut. Col., C. E. Blunt, Corps of Engineers.-This work occupies an important strategic point for the defense of the northern frontier. It remains the same as last reported, except additional adornment of the grounds by the city of Buffalo, under act of Congress approved July 11, 1870. Nothing has been done by the United States upon the fort during the past year, and nothing is proposed for the present fiscal year, there being no funds available. No preparations have been made or are intended for any change in the armament. No appropriation was made for the fiscal year ending June 30, 1877. No appropriation asked for next fiscal year. Fort Niagara, mouth of Niagara River, New York, in charge of Maj. John M. Wilson, Corps of Engineers until December 1, 1875; since that date in charge of Maj. Walter McFarland, Corps of Engineers.-This work is situated at the mouth of the Niagara River, commanding its debouch into Lake Ontario. This work remains in the same condition as at the close of the last fiscal year. The main approach to it has been damaged by water, but is in the course of repair. No appropriation was made for the fiscal year ending June 30, 1877. Fort Ontario, mouth of Oswego River, New York, in charge of Maj. John M. Wilson, Corps of Engineers, until December 1, 1875; since that date in charge of Maj. Walter McFarland, Corps of Engineers.-This work protects the city of Oswego from a sudden attack or coup de main, or the levy of a contribution by a small force of an enemy on shipboard. This work remains in the same condition as at the close of the last fiscal year. No work has been done, and no money expended upon it, except for minor repairs and pay of watchman. Nothing has been done toward preparing this work for its armament. No appropriation was made for the fiscal year ending June 30, 1877. Fort Montgomery, outlet of Lake Champlain, New York, in charge of Lieut. Col. John Newton, Corps of Engineers.-This work occupies an important strategic point, and commands the entrance to Lake Champlain from the Richelieu or St. John River. During the year the parade was graded as far as practicable, new bridge constructed and placed in the main postern, and the repair of the causeway, together with the sodding of parapet of curtain, (3,) has been commenced. Six hundred yards of earth and gravel were employed in grading parade. No appropriation was made for the fiscal year ending June 30, 1877. Fort Knox, Bucksport, Penobscot River, Maine, in charge of Lieut. Col. J. C. Duane, Corps of Engineers.-This work, situated at the narrows of the Penobscot River, furnishes a defense for the city of Bangor and other towns bordering the Penobscot, and renders the river available as a secure harbor of refuge for the shipping of the extensive eastern seacoast. The condition of this work remains unchanged, no operations having been carried on during the past fiscal year, except for the necessary care and preservation of the property. No appropriation was made for the fiscal year ending June 30, 1877. Fort Popham, Kennebec River, Maine, in charge of Lieut. Col. J. C. Duane, Corps of Engineers.-This work defends the entrance through the mouth of the Kennebec River to the rich valley of this river, the cities of Bath and Augusta, and the United States arsenal at the latter place. The condition of this work remains unchanged, no operations having been carried on during the past fiscal year, except for the necessary care and preservation of the property. No appropriation was made for the fiscal year ending June 30, 1877. Fort Gorges, Portland Harbor, Maine, in charge of Lieut. Col. J. C. Duane, Corps of Engineers.-This work is one of the series of forts designed to defend the harbor and channels leading into the harbor of the important strategic position occupied by the city of Portland. |