REPORT ON THE MAGNETIC AL RESULTS. 13 



generally occupied, and on account of the large range of magnetic latitude embraced, 

 a voyage from England to the Cape is one of the most useful for testing the magnetic 

 condition of a ship. Full advantage was taken of the visit to Table Bay for ascertain- 

 ing the various constants of the deviation of the compass, and the relative magnetic 

 instruments, and tables of weight equivalents, observed in order to test the magnetic 

 stability of the deflectors in the Fox circles. Leaving the Cape, the track now lay by 

 Prince Edward Island and the Crozets to Kerguelen Island ; thence southward to 

 near the Antarctic Circle, the vessel being swung in lat. 63° 30' S., long. 90° 47' E., for 

 observations of the magnetic elements, and thus in probably the most southerly position 

 since the days of Ross in the "Erebus" and "Terror," and very near the track of the 

 " Pagoda" in the year 1845. During this short trip into the Antarctic regions, and the 

 subsequent north-easterly track followed to Melbourne, evidence was obtained of 

 decided change going on in the declination and inclination, but nothing of the 

 remarkable character observed near Cape Horn as regards the inclination. 



Having made observations at the well-known stations of Melbourne and Sydney, the 

 ship now traversed portions of the Western Pacific, which are almost blank in Sabine's 

 maps. These were from Sydney, N.S.W., to Wellington, N.Z., northward to the 

 Friendly and Fiji groups of islands, then southward of the New Hebrides to Cape York 

 —one of the stations visited by H.M.S. " Rattlesnake" in 1848 and H.M.S. " Hecate" 

 in 1863 — and amongst the islands of the Eastern Archipelago to Manila and Hong Kong. 

 Returning southward by way of Samboangan to the Admiralty Islands and then north- 

 ward to Yokohama, the North Pacific was crossed about the parallel of 36° N. to 38° N. 

 till the meridian of 155° W. was approached, when a southerly course brought the 

 vessel to the Sandwich Islands, and on to Tahiti. Near these islands the ship was 

 swung with the object of observing the ship's magnetic constants, which were liable to 

 modification, due to the large change of magnetic latitude. From Tahiti to the parallel 

 of 40° S., a south-easterly course was followed, and along that parallel until the time 

 arrived for turning more directly towards Valparaiso. After obtaining base observations 

 at Valparaiso, and swinging, the route now lay towards the island of Juan Fernandez, 

 where the inclination and force were observed, and then by way of the Gulf of Penas 

 and the Patagonian Channels to Sandy Point, Magellan Strait. 



Reviewing the route traversed by the Challenger in the North and South Pacific 

 Oceans, it may be remarked that the observations there made formed one of the most 

 valuable parts of the contribution to terrestrial magnetism obtained in her ; for, follow- 

 ing a line drawn along the east coast of Australia to Cape York and then across to 

 Hong Kong, other observers had already done good work. Similarly, the lines of equal 

 magnetic value for the west coasts of North and South America were well known. But 

 the novel and valuable parts of the work consisted of the lines of observation from 

 Wellington to Tongatabu, and Fiji— from the Admiralty Islands to Japan, and the mid- 



