128 



SCmNGE. 



[Vol. IX., No. 210 



the astronomical determinations of latitude, rising 

 as high as forty-five seconds of latitude in the rel- 

 ative positions of stations on neighboring islands. 

 The study of these discrepancies shows them to be 

 due to local deflections of the vertical in conse- 

 quence of the powerful attraction of our great 

 mountain-masses. The error produced appears to 

 be greater than in any other part of the world in 

 proportion to the extent of the geodetic work. A 

 discrepancy in longitude of sixty seconds is found 

 to exist between Kailua and Honolulu, 150 miles 

 distant. These longitudes were determined by 

 the British transit expedition, transporting twelve 

 chronometers three round trips between the sta- 

 tions. The mountains of these islands rise above 

 the sea from 4,000 to 14,000 feet. But being sur- 

 rounded by a depth of ocean of, say, 25,000 feet, the 

 masses are really from 30,000 to 40,000 feet high, 

 fully accounting for the extraordinary deflection 

 of the vertical. Twelve stations have been selected 

 whose positions are precisely determined, and which 

 lie on opposite sides of their respective islands. 

 Mr. Preston will occupy each one, so as to secure 

 at least one hundred observations of pairs of stars. 

 It is believed that a study and comparison of the 

 discrepancies between the latitudes obtained will 

 enable a standard latitude to be determined for the 

 whole group, very closely approximating to the 

 true latitude. 



No precise determination of longitude can pos- 

 sibly be obtained until there is cable communica- 

 tion between Honolulu and the continent. It now 

 seems probable that such communication will soon 

 be established. Mr. Preston's work will then be 

 available in corrections to determine a standard 

 longitude as well as latitude for this group. When 

 these corrections for the latitude and longitude 

 are applied to the transit of Venus station at 

 Honolulu, it seems not unlikely that better re- 

 sults may be obtained from the work done by the 

 British transit expedition. 



A panorama of the caldera of Kilauea goes to- 

 day to the United States for public exhibition. It 

 is an accurate representation of the great enclos- 

 ure, and of the interior active lakes, as seen at the 

 period of culminating action shortly before the 

 periodical collapse which took place last year. 

 The work is by an eminent artist, Jules Tavernier, 

 who is particularly successful in vivid representa- 

 tion of incandescent lava. The whole is lifelike 

 and realistic. Although startling, it possesses a 

 high scientific value, far beyond a mere popular- 

 izing of the subject. 



Since the collapse, the lava has re-appeared in 

 force, and is slowly rising in the lakes, already 

 presenting brilliant exhibitions. After a period of 

 the highest activity, the lakes suddenly sank out 



of sight, leaving deep pits, the bottoms of which 

 were 700 feet lower than the previous level of 

 liquid lava. The surveyor-general embraced the 

 opportunity for a precise survey of Kilauea and 

 its branch craters, which has been completed. It 

 will probably be several years before any thing 

 like the recent high level of lava is again attained. 

 A remarkable phenomenon still proceeding has 

 been the uplifting from the bottom of the pit, as 

 if by colossal jack-screws, of a veritable mountain 

 island of lava more than 500 feet in diameter and 

 150 feet high, around which the liquid lava flows. 

 This permanent island has already risen some 300 

 feet within seven months. The best facilities are 

 now given for access to the crater, involving five 

 days' absence from Honolulu, at the cost of fifty 

 dollars, covering all transportation, hotel fare, and 

 guides, with two days at the crater. K. 



Honolulu, Jan. 18. 



GEOGRAPHICAL NOTES. 



Asia. 



Dr. A. Bunge and Baron E. Toll have returned 

 form their journey to the New Siberian Islands. 

 They have made valuable collections and observa- 

 tions on the five islands of this group, which of 

 late became so famous by the hazardous boat 

 journey of the Jeannette crew. The results of this, 

 the first scientific expedition to these islands, will 

 be of great interest. 



There are new reports on Potanin's expedition 

 to southern Mongolia. His return was announced 

 in the St. Petersburg letter of last issue. Potanin 

 left the district of Koko-Nor on June 25, 1886, 

 crossed the desert of Gobi on a previously un- 

 known route from south to north, and discovered 

 four parallel chains of mountains, which form the 

 south-eastern continuation of the Altai system. 

 The journal of the Imperial Russian geographical 

 society contains a report on his last explorations 

 in the district of Koko-Nor. He explored that 

 part of the Nan-shan mountains which separates 

 the country drained by the Hoang-ho fj"om the 

 plains of southern Mongolia. It is composed of 

 three mountain ranges, with passes 12,800 feet in 

 height, and intermediate valleys at an elevation of 

 10,000 feet. On his way north he fell in with the 

 Jegurs, a tribe hitherto unknown. Potanin sur- 

 veyed the whole country he traveled over, and 

 determined the position of seven places by astro- 

 nomical observations. His companion, the natu- 

 ralist Beressowski, will stay near Kiachta until 

 next winter in order to complete his collections. 



Mr. E. Michaelis, in Nature of Dec. 16, states 

 that traces of the ice-period are found in the 

 southern parts of the Altai Mountains. Farther 



