142 COSMOS. 



the part in the sea of Molucca and Japan) can scarcely be 

 followed as far as 62° in the southern hemisphere. This 

 starting-point lies farther west from Van Diem en's Land 

 than had hitherto been conjectured, and the three points at 

 which Sir James Ross crossed the curve of no variation, on 

 his Antarctic voyage of discovery in 1840 and 1841,* are 

 all situated in the parallels of 62°, 54° -30, and 46°, be- 

 tween 133° and 135° 40^ E. long., and therefore mostly in 

 a meridian-like direction running from south to north. In 

 its further course, the curve crosses Western Australia from 

 the southern coast of Nuyts' Land, about 10° W. of Ade- 

 laide, to the northern coast, near Vansittart River and 

 Mount Cockburn, from whence it enters the sea of the In- 

 dian Archipelago in a region of the world in which the in- 

 clination, declination, total intensity, and the maximum and 

 minimum of the horizontal force were investigated by Cap- 

 tain Elliot, from 1846 to 1848, with, more care than has 

 been done in any other portion of the globe. Here the line 

 passes south of Flores and through the interior of the small 

 Sandal-wood Island,! i" a direct east and west direction, 

 from about 120° 30^ to 93° 30" E. long., as had been ac- 

 curately demonstrated sixteen years before l3y Barlow. From 

 the last-named meridian it ascends toward the northwest in 

 9° 30" S. lat., judging by the position in which Elliot fol- 

 lowed the curve of 1° east variation to Madras. We are 

 not able here to decide definitely whether, crossing the 

 equator in about the meridian of Ceylon, it enters the con- 

 tinent of Asia between the Gulf of Cambay and Guzurat, or 

 farther west in the Bay of Muscat,J and whether, therefore, 

 it is identical^ with the <:urve of no variation, which appears 



* Sir James Eoss, Op. ciL, vol. i., p. 104, 310, 317. 



t Elliot, in the Phil. Transact, for 1851, pt. i., p. 331, pi. xiii. The 

 long and narrow small island from which we obtain the sandal-wood 

 {tschendana, Malay and Java; tschandana, Sanscrit; ./sa?2c?e/, Arab), 



X According to Barlow, and the chart of Lines of Magnetic Declina- 

 tions computed according to the theory of Mr. Gauss, in the Report of 

 the Committee for the Antarctic Expedition, 1840. According to Bar- 

 low, the line of no variation proceeding from Australia enters the 

 Asiatic Continent at the Bay of Cambay, but turns immediately to the 

 northeast, across Thibet and China, near Thaiwan (Formosa), from 

 whence it enters the Sea of Japan. According to Gauss, the Aus- 

 tralian line ascends merely through Persia, past Nishnei-Novgorod to 

 Lapland. This great geometrician regards the Japan and Philippine 

 line of no variation, as well as the closed oval group in Eastern Asia, 

 as entirely independent of the line belonging to Australia, the Indian 

 Ocean, Western Asia, and Lapland. 



ij I have already elsewhere spoken of this identity, which is based 



