380 Tranmctions. — Geology. 



Hochstetter, " With the beginning of volcanic action, by which 

 the tuff-cones were formed, a slow and gradual upheaving of 

 the whole isthmus seems to have taken place, so that the latter 

 eruptions" — by which the scoria-cones were formed — "were 

 supramarine." 



There remains one question of interest which I should like 

 to notice — the question of the age of these volcanoes. On this 

 point we may be certain that, although the last of them was 

 probably extinct before the advent of the Maori, still they are 

 of comparatively modern date. They distinctly overlie all 

 other formations in the neighbourhood, being the latest or 

 surface-deposits, and containing, mingled with their materials, 

 fragments of the Waitemata beds upon which they rest. The 

 fresh and recent appearance of the scoria and lava, the un- 

 altered angle of slope of the sides of the hills, the fact that the 

 lava-streams have everywhere followed valleys and depressions 

 in the surface of the land which exist at the present day, all 

 show that these volcanoes are of geologically recent date, and 

 that since the cessation of volcanic activity the general con- 

 tour and surface-features of the land have remained unaltered. 

 We conclude, therefore, that this activity dates from Pleistocene, 

 if not later or recent times. 



Art. XXXII. — On the Prospects of finding Workable Coal 

 on the Shores of the Waitemata. 



By James Pakk, F.G.S., Lecturer, Thames School of Mines. 



[^Read before the Auckland Institute, 22nd June, 1891.] 



The recent reported discovery of a thin, irregular seam of 

 coal in the cliffs near Northcote has again directed attention 

 to the probable existence of workable coal in the vicinity of 

 the City of Auckland. The great economic importance of this 

 question has long engaged the attention of the Director of the 

 New Zealand Geological Survey ; and during the past ten 

 years a number of surveys have been undertaken by the 

 officers of his department with the view of collecting sufficient 

 data to definitely determine the relation existing between the 

 Waitemata beds and the New Zealand coal-bearing series. 



In the years 1879, 1880, and 1881 Mr. Cox, late New 

 Zealand Assistant Geologist, examined the country extending 

 northwards from the Auckland isthmus to Whangarei on the 

 east coast and the Upper Kaipara on the west. He arrived 

 at the conclusion that the Waitematas, as typically developed 



