4G6 SCIENTIFIC RECORD FOR 1883. 



London, and Washington Laving been left in charge of the Coast Sur- 

 rey, advantage was taken of the presence of observers skilled in pen- 

 dulum work with the expeditions for the observation of the transit of 

 Venus and of the total solar eclipse of May G, 1883, to obtain results 

 for gravity at widely separated stations. Observations were accord- 

 ingly made at Auckland, New Zealand 5 Sydney, New South Wales ; 

 Singapore, Tokio, Caroline Island, Honolulu, (at a station in Maui occu- 

 pied by De Freycinet in 1819,) and at San Francisco. 



As indicating the widely spread interest in geographical study, ref- 

 erence may be made to a list of geographical societies and geographical 

 magazines recently published iu the ninth volume of the Geographi- 

 scher Jahrbuch, the former numbering seventy-nine and the latter one 

 hundred and nineteen. 



HYDROGRAPHY. 



The only original survey of foreign coasts prosecuted under the di- 

 rection of the United States Hydrographic Office during the year has 

 been the continuation of the survey of the Pacific coast of Central 

 America by the officers of the United States steamer Ranger. 



Lieut. Commander Z. L, Tanner, in the United States Fish Com- 

 mission steamer Albatross, has performed a most valuable work in run- 

 ning lines of soundings during the last winter in the Atlantic Ocean 

 and Caribbean Sea, and disproving the existence of alleged shoals and 

 dangers which have for years disfigured the charts. The details of the 

 work will properly be included in the summary for 1884. 



The United States Coast Survey have continued the deep-sea explo- 

 rations which have been prosecuted for several years past in the west- 

 ern part of the North Atlantic Ocean. During the winter of 1882-S3 a 

 systematic examination of the ocean bed between Bermuda and the 

 Bahamas was made, extending to the eastward as far as St. Thomas. 

 Numerous deep-sea soundings and dredgings were made, with observa- 

 tions of surface, serial, and bottom temperature. One most noteworthy 

 result of this cruise, which was performed by the steamer Blake, com- 

 manded by Lieut. Commander W. H. Brownson, U. S. N., was the 

 finding of the great depth of 4,561 fathoms, or 5.2 statute miles, nearly, 

 about 75 miles to the northward of Porto Rico. The bottom temperature 

 was found to be 364° F., and the specimen-cup brought up brown ooze. 

 This is believed to be the greatest depth from which bottom has been 

 brought up. The souudiDg was made with one of Commander Sigsbee's 

 piano-wire sounding machines. 



The British Admiralty have employed nine vessels, with fifty-seven 

 officers and four hundred and sixty-eight men, in surveying the shores 

 of the United Kingdom, the China Sea, Korea, Borneo, islands in the 

 Western Pacific Ocean, Australia, Newfoundland, the Bahama Islands, 

 the Bio de la Plata, and the Straits of Magellan. A careful examina- 

 tion of the Straits of Sunda was also made to ascertain and lay down 

 the chauges caused by the Krakatoa volcanic eruption. 



