Voyage of Capt. Sir James C. Ross to the Antarctic. 321 



The westerly variation gradually diminished during this run 

 until August 8th, when in lat. 46° S., and long. 134| R, they 

 crossed the line of no variation and then the easterly variation 

 as rapidly increased. " The line of no variation, which passes 

 through Australasia, has undergone very little change of position 

 during the last sixty years ; and it seems probable that the vari- 

 ation on this spot is about as fixed as on the coast of America. ?; * 

 u We have also reason to believe that at the Cape of Good Hope 

 where the westerly variation has been regularly increasing ever 

 since about the year 1600, when the line of no variation passed 

 through it, at the rate of seven and eight minutes annually, it 

 attained its maximum in 1840." 



A terrible storm, August 12th, tore their canvas into ribbons, 

 but they arrived safely in the river Derwent, in Van Diemens 

 Land, August 16th, and to their great joy found that the Terror 

 had arrived the day before them. They remained there two 

 Months, and in that time established a permanent observatory 

 called Rossbank by Sir John Franklin, the governor of the Col- 

 ony. It is in lat. 42° 52' 27-4" S., long. 147° 27' 30" E., one 

 hundred and five feet above mean tide level, on vast strata of 

 sandstone. Lt. Shay and a party were left to make observations 

 during the absence of the ships in the south. 



The mean magnetic dip was 70° 40' S., and the variation in 

 May, 1841, 10° 24' 24" E. 



The convicts, two hundred in number, who labored in the ex- 

 cavation of the foundation rock, and the erection of the fixtures, 

 manifested great zeal, and volunteered to labor all night in order 

 to finish the building in season for the observation day, August 

 27th ; and before this time every thing was ready : the whole 

 ^ork, including the delicate adjustments of the instruments, was 



accomplished in nine days.f 



Throughout the twenty-four hours of the 27th and 28th of 

 August, a record was kept of observations in the three elements, 



* Barlow in Phil. Uraaa for 1837, p. ft. 



t In connexion with this resilience in Van Diemens Land, a statement is intro- 

 duced, respecting the comparative observations and merits of the British, French 

 ^d American squadrons of discovery, under their respective commandei aptain 

 R° D'Urville and Wilkes. It is to be regretted that so honorabh a man as Sir 

 James C. Ros and that too after an .appropriate expression of genei inn ts, 



should have thrown out an imputation of intended interference in the line of discov- 

 € *y, whj. pt. Will- has shown by reference to dates and duenmeir to be en- 



tirely without foundation as regards the American squadron | I we h eve it baa 

 never been proved to be true, us i jards the French) ; moreover the report is wis y 

 untrue, that the British Exp lition led over any part of the r< i where land 

 ^as laid <| own by Captain Wilkes, the route of Captain Ross t. to the 



eastward But as these matt* have been already discus I in the prints— (and in 

 this Journal, vol. v, p. 288, ii series) we do not incline to go over the ground again, 

 but proceed'with the more agr< ible task of setting forth the valu; le results ob- 

 tained by the British Expedition as recorded in the interesting volumes before us. 



Second Series, Vol. VII, 'No. 21.— May, 1849. 41 



