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Likewise, both by a sheet of astronomical observations made by Bering which came to me later, and by the same letters of M. de l'Isle, I knew that the mouth of the river of Kamtchatka was found by astronomical determination to be in latitude 56° and some minutes.
"Bering in his navigation doubled the southern point of this continent [Kamshatka] in latitude 51° 10′, as is expressly noted in the sheet of observations which is now before me.
But though the solution of the difficulty in the case of the Land of Jeco may be very simple and natural, yet it was not obvious to me, it may be said, for Bering's voyage and observations caused me to recur to this subject, and I can no longer doubt that the eastern coast of Tartary should be moved to the east as far as the maps of the Jesuits first indicated; for although M. de Strahlenberg in his excellent map of Siberia shows only 65° of longitude between Tobolsk and Okhotsk, and there are even less in de l'Isle's map of Tartary, yet Bering's map indicates that there are 74°. "It was found that it (Ohkotz) is 25° off of the meridian of Peking, which the observations of P. Gaubil placed in 113° fifty-odd minutes from Paris, so that it closely approximates the 139° which we have found it to be from Bering's observations. This determination does not differ much from the result of some astronomical observations, which, as I learn from China, M. de l'Isle, now in Russia, contemplated using in order to ascertain approximately the longitude of Kamtchat. The observation upon which I place the most dependence, and which likewise gives the greatest difference, is of an eclipse of the moon of February 25, 1728, of which the end was observed on the west coast of Kamtshat in latitude 52° 46′ N., Sirius having an altitude of 19° 18' to the west, wherefrom M. de l'Isle calculated that the true time answered to 6h. 52m. p. m.
"This eclipse, the end especially, fell throughout Europe in the daytime, but having been observed at Carthagena, West Indies, by D. Jean Herrera, where it ended at 3h. 34m. a. m., a difference of Sh. 42m. is deduced between the meridians of Carthagena and the coast of Kamtshat."
It is thus evident that Bering observed an eclipse of the moon in Kamshatka, and that the observations came into the hands of M. d'Anville.
JANUARY 21, 1892.
A. W. G.
HEIGHT AND POSITION OF MOUNT ST. ELIAS.
ISRAEL C. RUSSELL.
(Laid before the Board of Managers December 11, 1891.)
The height and position of Mount St. Elias have been measured several times during the past century with varying results. The measurements made prior to 1891 have been summarized and discussed by W. H. Dall, of the U. S. Coast and Geodetic Survey.* The various results obtained are shown in the following table. With the exception of the position determined by Malaspina and the measurements of 1891, they are copied from Dall's report. Height and Position of Mount St. Elias.
The position given by Malaspina is from a report on astronomical observations made during his voyage, which places the mountain in longitude 134° 33′ 10′′ west of Cadiz. Taking
*Rep. of the Superintendent of the U.S. Coast Survey for 1875, pp. 157–188. Memorias sobre las obversaciones astronomicas hechas por les navegantes Españoles en distintos lugares del globe; Por Don Josef Espinosa y Tello. Madrid, en la Imprente real, Ano de 1809: 2 vols., large S°; vol. 1, pp. 57-60. My attention was directed to this work by Dr. Dall, who owns the only copy I have seen.
the longitude of Cadiz'as 6° 19′ 07′′ west of Greenwich, the figures given in the table are obtained.
The data from which the various determinations made previous to 1874 were obtained have not been published. The observations made by Messrs. Dall and Baker, of the U. S. Coast and Geodetic Survey, are published in full in the annual report of that Survey for 1875, already referred to. The observations made by myself last summer as a part of the work of an expedition sent to Mount St. Elias by the National Geographic Society and the U. S. Geological Survey, from which the height and position of the mountain have been computed, are as follows:
A base line 16,876 feet long was measured on the beach at Icy bay. The line, with the exception of section C to D, as shown below, was measured three times in sections of about 3,000 feet each. The distances given below in columns 1 and 2 were obtained with a 100-foot steel tape, and those given in column 3 with a 300-foot iron wire. These are rough measurements, made without the use of a plumb-bob and without taking account of temperature. The ground was quite smooth, with a rise of about five feet in the center; but section Cto D was crossed by a stream channel about 300 feet broad and twenty feet deep. Throughout much of the distance the ground was covered with grass, which was only partially cleared away. The stations at the ends of the line were ten feet above high tide. The bearing of the line from the western base was S. 89° E., magnetic.
The measurements of angles were made with a gradienter reading by vernier to minutes. The error of the vertical arc was-3', and remained constant during the observations.
From these observations the following angles between the base line and the line of sight to the summit of Mount St. Elias are obtained. The correction for error of vertical circle has been applied to the angles of elevation.
The known elements of the triangle from which the distance of St. Elias from the ends of the base line may be determined
These data were sent from the field to the Secretary of the National Geographic Society, and, in connection with other measurements made at the same time, have been computed by