No. 55. Report to the assistant in charge of the Coast Survey office, on the electrotyping operations of the Coast Survey, by George Mathiot, electrotypist. No. 56. Report of Lieutenant Commanding W. A. Bartlett, United States navy, assistant in the coast survey, to the Superintendent, of the examinations of the reefs in Hell Gate channel, and changes produced by blasting. No. 57. Report of the Superintendent of the Coast Survey to the Secretary of the Treasury, upon an examination in reference to a lighthouse at Humboldt harbor, California, made by Lieutenant Commanding James Alden, United States navy, assistant in the coast survey. No. 57, bis. Letter of the Superintendent of the Coast Survey to the Hon. Joseph Grinnell, of the Committee on Commerce, House of Representatives, communicating a report of Lieutenant W. A. Bartlett, United States navy, assistant in the coast survey, on the importance of a light-house at Humboldt harbor. LIST OF SKETCHES ACCOMPANYING THIS REPORT. Sketch of progress, Section 1. Nantucket shoals, re-engraved. Sketch of Holmes' Hole, showing proposed beacon. Sketch of progress, Section, 3. C, No. 2. Entrance Chesapeake. C, No. 3. Fishing Battery. Gulf Stream soundings. D, No. 5. Beaufort harbor. Point Judith to N. York. D, No. 6. Progress of survey of Cape Fear river and vicinity. E. E, No. 2. E, No. 3. E, No. 4. Sketch of progress, Section 5. Sketch of progress, Savannah river. Sketch of progress, north and south Edisto and St. Helena Savannah city. شت J. Sketch of progress, Sections 10 and 11. J. No. 2. Mare Island straits. J, No. 3. Point Conception. J, No. 4. Point Pinos. J, No. 5. Trinidad bay. J, No. 6. Entrance San Francisco. J. No. 7. San Diego. J, No. 8. Humboldt bay. J. No. 9. Sketch of progress San Francisco. J, No. 10. Sketch of progress San Diego. J, No. 11. Point Pinos view, incorporated into McArthur's chart. J, No. 12, 13, 14. McArthur's chart, 4th edition. K. Mouth of the Columbia river, showing site of light-house, scale 200000. K, No. 2. Cape Hancock. K, No. 3. Mouth of the Columbia river, scale o X. Plate showing the electrotype apparatus. APPENDIX No. 1. Distribution of the parties of the Coast Survey upon the coast of the United States, during the surveying seasons, in the different parts of the coast, from November, 1850, to November, 1851. No. of sections of survey. Limits included in several No. of parties in section. Operations. Persons conducting the operations. Localities of the several operations. I Passamaquoddy bay to Point 1 Primary triangulation and astronomical and magnetic observations. 2 23 Magnetic observations A. D. Bache, superintendent; Lieut. J. E. Hilgard, assistant C. O. Boutelle, assistant; Brevet 4 Secondary triangulation - Captain T. J. Cram, United States Mount Pleasant, Maine, occupied for geodetic and Saco, Kennebunk, and Portland harbors. Sub-section from Portsmouth, New Hampshire, to Reconnaissance for secondary triangulation, Casco Newburyport harbor, Massachusetts. South and east shores of Cape Ann, Massachusetts, Chatham and vicinity, and Wellfleet, Cape Cod, Hudson river, from limits of former work. (Part of season; see also Section III.) Re-survey of Sandy Hook to determine its changes. (Part of season.) Survey for ranges for Flynn's Knoll and Swash Verification on south side Long Island, from Nea- Off-shore work and tides and currents, between Minute survey of Way's reef, Pot Rock, &c., at Observations of latitude and azimuth at Causten's station, near Georgetown, D. C. (Part of season; see also Section I.) Continuation of triangulation of Chesapeake, and Longitude observations at Seaton station. To connect triangulation of Chesapeake and outer coast. (Part of season; see also Section IV.) Point Judith to Cape Henlopen, including the coast of Connecticut, New York, New Jersey, Pennsylvania, and Delaware. III Cape Henlopen to Cape Henry, including the coast 1 of Delaware, Maryland, and Virginia. 2 |