522 PROCEEDINGS OF SECTION E. 



(as is usually the case on the mountain) took place. On the day previous- 

 to our exploration of the north end a careful aneroid observation at 

 the " Station " made it 602ft. above the camp, which was, as well as 

 we could judge from several readings, 4,408ft. above sea-level, the 

 glass being particularly steady on this occasion. 



On the following day we had again a steady barometer, and 

 taking our camp as a datum point, we left in the morning for our 

 obj ective at the north end. En route we explored two of the interesting 

 " trough " valleys, which were on our track, and discovered three 

 small tarns, playing their part in the stream-system of the plateau, 

 and to which we gave names. 



At raid-day we arrived at the deep cross valley, or transverse 

 depression, which divides the moorland into two divisions, and which 

 will be referred to hereafter as the " Divide," or " Dividing Valley." 

 Crossing this, we ascended a talus-floored valley, which divides the 

 heights and crags of the eastern escarpment from the high hills of the 

 central portion of this area, and halted for luncheon at the foot of the 

 eastern slopes of the latter. 



The ascent of the two highest ridges in the group was made in the 

 afternoon by Mr. Giblin and the writer, the higher and more distant 

 being chosen by the former. Only one observation was taken, the 

 reading being, when referred to our datum point, 148ft. (1) higher than 

 the ordnance station (5,010ft.). This altitude, however, being the 

 the result of a single reading of the barometer, was set down as 148ft. 

 ± 30ft. The height of the lower ridge was approximately 60ft. less 

 than the above. 



The second expedition was carried out in March of this year (1907), 

 for the purpose of again taking aneroid readings of the altitude of the 

 higher summit, (2) and exploring the valleys and fells of the northern 

 " Division." 



On this occasion, too, we had a steady barometer, and careful 

 note was taken for an hour, at intervals of 15 minutes, of the readings, 

 and repeated in the afternoon. The result of these led us to fix the 

 altitude of the peak provisionally at 130ft. ± 30ft. higher than the 

 old station of the Trigonometrical Station of the " Fifties." 



The members of this party were Mr. L. Giblin, Messrs. Allen 

 Giblin. E. L. Piesse, and the writer, to whom these well-known Tas- 

 manian mountaineers rendered most valuable and indispensable, 

 service throughout the whole of the trip. While the writer made a 

 compass triangulation of the fells and adjacent heights, Messrs. Giblin 

 and Piesse, who have both made a study of the aneroid in connection 

 with its variations and uncertainties as to hysterisis and weather 

 conditions, took the readings. It may therefore be assumed that 

 when the height of the Giblin Fells is accuratelv fixed by theodolite 

 the altitude of the peak will be found not to differ considerably from 

 our provisional determination. 



(1) Or 750ft. above the camp altitude taken that morning, which corresponded 

 with the reading in the evening on our return. 



