316 T. G. TAYLOR AND D. MAWSON. 
2,830 feet above sea level, rising about 1,000 feet above 
the surrounding country. It consists of a syenite allied to 
Bostonite (Harker, p. 117) consisting chiefly of orthoclase 
x s % 
Bate ¥ 4 Gibraltar Trug: Sn 
x oe) SO Rae | 
' + x 
ae es x 
i; ai 
Fig. 4—Map of the district to the west of the Gib; showing volcanic necks and dykes. FP 
(For legend see Plate 25.) a | 
