152 DISCOVERY REPORTS 



ance of Admiralty officials. She is rigged as a barque with fore, main and mizen 

 masts, and her principal dimensions are as follows: 



Length overall 



Length on water line from fore edge of stem to axis of rudder . . . 



Extreme breadth ... 



Depth amidships from top of ceiling to top of upper deck beam 



Designed draught ... 



Designed displacement at 16 ft. o in. water line, about 1600 tons 



Construction. The ship was constructed of wood throughout with the exception of 

 the fastenings, which were mostly of galvanized iron, except within a radius of 30 ft. 

 of the magnetic centre or magnetic observatory, where they were of naval brass. 

 The framing of the vessel generally was of English oak, grown to form wherever 

 practicable; the beams on the main deck were, however, of pitch pine. The main 

 planking was of Canadian elm below water and pitch pine above water, varying in 

 thickness from 7 in. at the keel to about 4 in. at the sheer. An outside sheathing or 

 doubhng of green-heart about 3Hn. thick was fitted fore and aft, extending about 1 1 ft. 

 below the water line except at the forward end of the vessel where it was extended 

 down to the keel at the forefoot as a special protection against ice. The inner bottom 

 planking was of Riga fir about 3^ in. thick, excepting below the clamps in the 'tween 

 decks where it was about 4 in. thick. The beam shelves and clamps were exceptionally 

 heavy, also the main waterways and inner waterways, resulting in the vessel having an 

 average general thickness of 2 ft. throughout her girth. 



The forefoot was of the most solid construction, with special ice protection extending 

 to about 5 ft. above the load water line. This protection consisted generally of oak 

 timbering built up behind the stem to a depth varying from 8 ft. at the head to about 

 ID ft. at the foot, and, on top of the wood, galvanized steel plates were also fitted to 

 reduce chafe as far as possible. Beams and heavy diagonal timbers, all of oak, were in- 

 troduced in the lower part of the vessel at the forward end to withstand ice pressure. 



The decks of the ship were of Dantzig fir, varying from 3^ in. in thickness on the 

 weather deck to zh in. on the lower-deck flats. The bulkheads — which were five in 

 number — were of wood throughout, with the exception of that at the forward end of 

 the boiler space, which was of steel to guard against deterioration due to heat from the 

 boilers. 



In the Original Design of the Vessel a topgallant forecastle was arranged forward, 

 and the entrance to crew space and galley in a house abaft the fore-mast. Between the 

 fore and main masts a magnetic observatory was built, with houses abreast of it on either 

 side, occupied mainly by laboratories, and with the bridge above. The entrance to the 

 wardroom was immediately abaft the magnetic observatory, and a large skylight for 

 light and air to the wardroom was placed amidships. 



The engine and boiler casings were of steel, situated between the main and mizen 



