REPORT OF THE CHIEF OF ENGINEERS. OFFICE OF THE CHIEF OF ENGINEERS, Washington, D. C., October 19, 1878. SIR: I have the honor to present for your information the following report upon the duties and operations of the Engineer Department for the fiscal year ending June 30, 1878: 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 106 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 by its organization, the employment of a number of scientists and assistant engineers has been necessary. Since last annual report the corps has lost by death two of its officers, Lieut. Col. John D. Kurtz, who died at Georgetown, D. C., October 16, 1877; and Capt. A. H. Burnham, who died at Lowell, Mass., September 12, 1877. One officer, First Lieut. Edgar W. Bass, resigned May 2, 1878, to accept appointment as professor of mathematics at the United States Military Academy. There have been added to the corps, by promotion of graduates of the Military Academy, two second lieutenants, whose commissions date from June 15, 1878, but who did not become available for duty till after the close of the year, and are, therefore, not included in the strength of the corps. On the 30th June, 1878, the officers were distributed as follows: On duty, Office Chief of Engineers, including the chief... On duty, Office Chief of Engineers, Public Buildings and Grounds, District of On duty, fortifications On duty, fortifications and light-house duty On duty, fortifications and river and harbor works. On duty, fortifications, river and harbor works, and light-house duty 1 3 3 14 On duty, river and harbor works.. 22 On duty, river and harbor works and light-house duty On duty, survey Northern and Northwestern Lakes and Mississippi River 1 5 11 1 On duty, explorations of country west of one hundredth meridian On duty with battalion of engineers On duty with battalion of engineers and fortifications On duty with battalion of engineers and at Military Academy On staffs of generals commanding divisions and departments and on river and Detached on duty with the General of the Army, generals commanding divisions Suspended Total 103 SEA-COAST AND LAKE-FRONTIER DEFENSES. During the past fiscal year work upon our sea-coast defenses has been limited to operations for the care and preservation of the works only, no appropriations being available to continue to completion the batteries already begun. 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 indorsed 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. The modification of the casemates of our masonry forts was at that time deemed premature, it being then thought preferable to await the further development of iron-clad fleets and their armaments and to take advantage of the experience of foreign nations. From 1869 to 1875, while appropriations for coast defense were granted by Congress, much progress was made in earthen barbette batteries for heavy guns and mortars; and further, a system of defense by torpedoes-a subject of continuous study up to this time-has been developed which only requires a sufficiency of material and trained men to put it into practice when needed. But torpedo defense, however efficient in itself, cannot stand alone; the torpedoes must be protected by shore batteries. Unfinished earthen batteries, however, provided with a small fraction only of the number of guns for which they were designed, and those of insufficient caliber, and mortar batteries without mortars, though aided by torpedoes, will form but a feeble defense against the powerful fleets prepared and now being prepared to take the high seas. The great powers of Europe do not place their reliance on barbette batteries. They believe in, and are constructing, casemated forts, some of which are provided with wrought-iron scarps and others with iron casemate-shields to protect the gun, and gunners serving it, both from direct and curved fire. This department, while recommending and urging the construction of barbette batteries as an initiatory means of obtaining by comparatively small expenditures a partial defense for the numerous exposed harbors of our coast, has always insisted that the efficient service of the large guns mounted in them would require high parapets and depressing or counterpoise carriages. It has also, from the beginning, looked forward to the ultimate conversion of some of our casemated forts, which would admit the change, for the reception of guns of the largest caliber, and to the possible construction of new works. Within the past two years, in furtherance of these views, a large casemated fort has been designed to take the place of old Fort Lafayette at the Narrows entrance to New York Harbor. Plans also have been prepared for modifying the casemates of Fort Schuyler on the East River, and for completing Fort Carroll on the approaches to Baltimore. The modification of other casemated works is now a subject of study. It will require much time and large expenditures to make the foregoing modifications, and to complete our barbette and mortar batteries and furnish them with suitable armaments. It would be but an act of prudence to make the beginning without delay. The disasters of the first three months of a war under the present condition of our defenses might cost the nation tenfold the expenditure that would be needed to thoroughly protect our coast against attack. Our great cities, New York, Philadelphia, Boston, San Francisco, New Orleans, Baltimore, and Washington, should they fall into the hands of an enemy, would suffer ten times more than the cost of all the forts necessary to secure them against such disaster. But such reverses would also be great calamities to the nation, crippling its war power. When the great change in ships and their armaments was initiated, Great Britain did not hesitate to appropriate $40,000,000 for the defense of its most important harbors, and in addition she has already expended about $60,000,000 upon her iron-clad fleet. We may well profit by her example. There is nothing so costly to a nation as a lack of preparation for war. In fact, to be prepared for war will often prevent it; and though we may not feel the daily imminence of war with great foreign powers, as England did, yet with incomplete or inadequately armed defenses for our great sea-port cities, even the attitude of belligerency, which we not unfrequently have to assume, has not the imposing effect it should have, nor is it accompanied with a justly founded self-confidence on our own part. The neglect of suitable preparation cost France many millions of treasure, a portion of her territory, and a great humiliation. The same must inevitably happen to the United States if it does not push forward its coast defenses and provide them with guns like those possessed not only by the great powers, but even by smaller nations. That our forts should be efficient we must have guns of power not inferior to those that will be brought to contend with them. These guns must have a protection—whether by earthen parapet and depressing carriage or by iron armor-no less efficient than that which protects the hostile gun. Our system of torpedo defense must rely upon forts for protection, otherwise it would be rendered harmless. It would be speedily destroyed by an enemy if one of its iron-clad fleets were suffered to approach it unopposed. It is, therefore, by the combination of the two systems, viz, the torpedo defense and shore batteries, that our harbors can be made secure against the powerful iron-clads of the present day in the event of a war with a maritime nation. It concerns the honor of the United States, when involved in controversy with other powers, to be able to appeal to the sword, but that appeal should be accompanied by the consciousness that the weapon appealed to would not be inferior to that held by the adversary. This relation of inferiority may at present exist though the adversary be a comparatively weaker power. We have the assurance that iron plates can be manufactured in this country equal in magnitude and not inferior in quality to those which fifteen years of experience have enabled the English rolling-mills to turn out. Congress has shown its interest in the material development of the resources of the country, and especially in reviving trade and relieving the working class, by liberal appropriations for river and harbor improvements. Might not the immediate undertaking, on an adequate scale, of the construction of efficient iron-clads, the manufacture of the so much needed guns of large caliber, and the now demanded renewal of revetment in iron of our most important sea-coast works, be not only a wise measure of national defense, but an incidental means of reopening our workshops and reviving one of our most important industries-the manufacture of iron? It is believed that the present time, when all kinds of materials and |