and plans of the various sites occupied by the army, and in the service of the pontoon trains for bridging the water-courses.
The army under General Banks had six officers attached to it, who constructed many field-works for the defense of particular localities, and under General Canby four officers, who conducted all the siege operations that ended in the capture of the permanent sea-coast defenses on Mobile Point and Dauphin Island.
General Steele has had two officers accompanying his army in its march through Little Rock to the Red River and back to Little Rock, calling for frequent use of the pontoon bridge trains in their charge and the construction of some field-works for the defense of particular strategic points.
The Department of the South, under Generals Gillmore and Foster, has had the services of three officers, who were most arduously engaged in the siege operations at Forts Gregg and Wagner, and in the demolition of Fort Sumter; and the Department of Virginia and North Carolina, under Generals Foster and Butler, has had the services of two officers, constructing the defenses of New Berne and Washington, N. C.
Such has been the disposition of the officers and their labors in their legitimate staff duties in the field. These several armies have also no less than nineteen engineer officers as commanders of troops, aides-de-camp, and assistant adjutants-general, holding rank as major-generals, brigadier-generals, and staff officers.
While these field duties have been performed by engineer officers, twenty-four others have been engaged in the construction of the permanent and temporary sea-coast defenses on the Atlantic, Gulf, Pacific, and lake coasts. Their labors have been arduous and unremitted, being necessarily compelled to superintend works so distant from each other that they were able to give but partial personal attention to any one.
The survey of the lakes has also progressed under charge of one officer, and the harbors on the lakes and Atlantic under another. The selection of a naval site on the Western waters is assigned to another, as member of a commission for that purpose, and two others are associated with the chief engineer in the various duties of the bureau, where many of the maps are compiled for the armies in the field.
During the year nine officers of the corps have been lost by death, all of whom have given their lives to the service of the country. The whole Army mourns the loss, among these, of the distinguished chief who for more than twenty-five years so worthily commanded the corps.
The total amount expended by the department for the year is $ 6,345,191.74. The amount appropriated by Congress for the prosecution of the works on which this sum has been expended, including the Military Academy, is $ 6,959,297.
The number of sheets of maps furnished during the year by the topographical branch of the department to the armies in the field throughout the United States was 20,938. Of sheets of the lake surveys, for commercial as well as military purposes and harbor improvements, there were distributed 3,688 sheets; making a total issue of 24,626 sheets.
For these supplies and for the instruments used in conducting operations to obtain these results, there has been expended the sum of $ 49,755.81.