Massachusetts, New York, and the coal and oil regions of Pennsylvania, in spring wagons with our own teams. CHAPTER II. Submarine Blasting,—Erie Harbor,—Dimon’s Reef, N. Y., —Coenties Reef, N. Y.,—Oil Wells, Penn. In the winter 1869, 1870, I received a communication from the engineer in charge, Major G. Clinton Gardiner, formerly of the United States Boundary Line Survey, concerning the harbor improvements in Erie, Penn., under W. A. Baldwin, General Superintendent of the Philadelphia and Erie Railroad, with a view to blasting in the harbor of Erie, so as to furnish from 15 to 17 feet of water for vessels laying alongside of their wharves, instead of carrying them (the wharves) into deep water; these operations were entirely successful, and I subjoin the report of Major Gardiner to General Parke, U. S. Engineer Corps, written previous to dredging. The certificates of Mr. Baldwin, Superintendent; F. J. Wilson, Ass’t Engineer; Chas. F. Dunbar, contractor for the dredging, follow Major Gardiner’s report. These certificates it will be observed, were given after a considerable portion of the rock had been removed by the dredging machine. LETTER FROM MAJOR G. CLINTON GARDINER TO GENERAL JOHN G. PARKE, Corps of Engineers, Washington City, D. C. OFFICE OF PHILADELPHIA & ERIE RAILROAD. Erie Harbor—August 2nd, 1869. To GENERAL JOHN G. PARKE, Corps of Engineers, U. S. A. My dear General: Some days ago I received a letter from Mr. Geo. M. Mowbray, who is the patentee of a most valuable improvement in the manufacture of Nitro-Glycerin. He being interested in having his material used in the improvements at Hell Gate, requested me to report upon the experiment in blasting at this place. Being unknown to General Newton, and having no time for a report, I take the liberty of writing to you on the subject.