INDUSTRIAL PROGRESS DURING THE YEAR 1876. cxxi 



principal ports, all sucli information coming to the knowledge of the 

 office is communicated. Seventy-five notices to mariners, embody- 

 ing information of changes in artificial aids to navigation, have been 

 published, as well as sixty-nine hydrographic notices of newly dis- 

 covered features in the earth's surface. 



As far as the limited appropriations made by Congress would 

 permit, new charts have been engraved and published. 



Sailing directions for the Pacific Ocean, the west coast of Africa, 

 a part of the coast of the Mediterranean, the Bay of Biscay, the 

 West India Islands, and for the coasts of Chili, Peru, and Bolivia, 

 have been published during the past year, or are ready for publica- 

 tion. 



Under direction of the Navy Department, the U. S. steamship 

 Tuscarora^ Commander J. N. Miller, has examined the depth of the 

 Pacific Ocean from the Sandwich Islands to the Fiji group, and 

 thence to Brisbane, Australia ; to determine if the laying of a tele- 

 graph cable is feasible from California to Australia. In the per- 

 formance of this work one hundred and seven soundings were made 

 with steel wire. Specimens of the bottom were obtained from near- 

 ly every sounding, and are now being examined. Of these soundings 

 the deepest was 3448 fathoms ; there being nineteen of less than 1000 

 fathoms, thirty-eight of from 1000 to 2000 fathoms, thirty-two from 

 2000 to 3000 fiithoms, and eighteen of over 3000 fathoms. 



The observations for the determination of secondary meridians in 

 the West Indies have been completed by the officers of the U. S. 

 steamship Gettysburg. 



The undertaking of systematic determinations of longitude by 

 the electric telegraph, wherever submarine cables extend, thus com- 

 menced by the U. S. Navy Department, has received much attention 

 and commendation from foreign officers. 



During the homeward voyage of the Gettysburg^ deep-sea sound- 

 ings were made in the intervals between those previously made by 

 H. B. M. steamship Challenger^ in every case confirming the Chal- 

 lenger'' s work. 



In consequence of errors known to exist in the geographical posi- 

 tions of the north coast of South America, the U. S, steamship Huron 

 has been ordered to determine the longitudes of about thirty sta- 

 tions along that coast, measuring the longitudes by chronometer 

 from the meridians of Port Spain (Trinidad) and Aspinwall, jirevious- 

 ly determined with great exactness by telegraph. 



The U. S. steamship Gettysburg^ while engaged in searching for 

 doubtful dangers in the eastern part of the North Atlantic Ocean, 

 has discovered a remarkable coral bank, about five miles in extent, 

 lying about one hundred and thirty miles to the westward of Cape 

 St. Vincent. The least water found on the bank thus far is thirty- 

 four fathoms, but there is probably less. 



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