LAKE SURVEY. The shore line of the great lakes and rivers following the prin cipal indentations is about 0,000 miles. The work to be done in surveys, soundings, etc., approaches in magnitude that of the Atlantic coast. The first appropriation to defray expenses was made in 1841 of $15,000. Previous to 1802 the largest annual appropriation had been $75,000, since which it has varied from $50,000 to $175,00O. The first charts were published in 1852, but they were only of charts of localities, as a general survey had not then been made. After this the work became more extensive. it is very much like the work on the Atlantic coast., and is performed by primary triangulation in the first place, to be followed by secondary and tertiary, and by hydrographic surveys. Some of the work has been intricate, requiring ninny nice mathematical processes. In some places where primary triangulations would have been difficult of direct application, as along the American shore of lake Huron, many points have been determined by a (mom • bhmtion of triangulation and astronomical work, On the lake Michigan shores many positions were obtained by carrying lines from known points. The work has been car
ried on with commendable energy, and a great portion of the triangulation has beets completed, and the hydrography of the harbors carried on to meet the demands of navi gation.
The following are the officers who have been in command of the work: Capt. W. G. Williams, T.E., 1841-45; licut.col. J. Kearney, T.E., 1845-51; capt. J. N. Macomb, T. E. , 1851-56; J Kearney, T.E., 1856-57; capt. G. Meade, T.E., 1857-01; col. J. D. Graham, T.E., 1861-04; col. and brevet brig.gen. W. F. Reynolds, engineers, 1864-70; major and brevet brig.gen. C. B. Comstock, 1870-81.