MARYLAND GEOLOGICAL SURVEY 117

the several triangulations made in after years. Hydrographic work
had not yet been begun. Topographical surveys were in progress in
charge of Assistant Geo. D. Wise, at the entrance of the Patapsco
river.

In his report of December, 1845, Professor Bache states: "Mate-
rials for a chart of the Patapsco river and Baltimore harbor will, it is
confidently expected, be ready for use this winter, and the chart will
at once be drawn and put in the hands of the engraver. The topo-
graphy has been executed by Assistants Gerdes, Hassler, Wise and
Cutts. Sheets Nos. 6 and 8 are completed, and on No. 9 considerable
progress made. No. 8 includes Baltimore City and adjacent country. "
Referring to sheet No. 8, Mr. Wise remarks: " Having found it im-
possible to reconcile the measured distance with printed plan of the
city (Poppleton's map presumably), it was found necessary to make
a detailed survey, especially of the part near the water. "

During 1845 the hydrography of the Patapsco river and Baltimore
harbor was begun and completed. Topographical work was continued
in the same localities during this year and 1846.

In 1847 engraving of the chart of the localities above named was
begun.

In 1848 magnetic observations were made at Fort McHenry.

Report of Professor Bache, December 27th, states: " Map of Balti-
more harbor and Patapsco river still in hands of engravers. "

"During the year a verification¹ of the topography of the city of
Baltimore was made by Assistant J. B. Gluck. "

Report of November 5th, 1851, mentions: "Map of Baltimore
harbor, etc., still in hands of engravers. "

During 1853 Assistant H. L. Whiting was engaged in verification
of topography of the Patapsco shores.

1854, a re-survey of the Patapsco river entrance was made by request
of the Engineer Department, U. S. A.; no considerable changes were
developed. With this the record of field operations by the Coast
Survey in the vicinity of Baltimore, prior to the Civil War, closes.

In July, 1863, by request of the military authorities at Baltimore,

¹ These verifications were in reality re-surveys.