ABSTRACT OF PROCEEDINGS. XXXI1x, 
Twenty-five volumes, 204 parts, 21 reports and 9 pam- 
phlets, total 259, received as donations since the last 
meeting were laid upon the table and acknowledged. 
The President announced that the Third Science Lecture 
1903, on ‘‘Water,’’ would be delivered by Prof. LIVERSIDGE, 
M.A., LL.D., F.R.S., in the Chemistry Lecture Theatre at the 
University, on Thursday, October 22nd, at 8 p.m. 
That the next meeting of the Australasian Association 
for the Advancement of Science would probably be held 
about January 6th, 1904, at Dunedin, N.Z. He mentioned 
that the Union Steamship Company would allow a discount 
of 20% off the usual fares to all members of the Association, 
and that the New Zealand Government had very generously 
offered free passes to members over all the railway lines 
for a month. Any information in connection with the 
meeting could be obtained on application to the Permanent 
Honorary Secretary (Professor Liversidge) at the Sydney 
University. 
THE FOLLOWING PAPERS WERE READ: 
1. ‘The Geology of the Mittagong District,’ by T. 
GRIFFITH TAYLOR and D. Mawson, B.E. [Communi- 
cated and read by Prof. T. W. EDGEWORTH Davin, 
B.A., F.G.S., F.R.S. | 
The authors show in this paper that the eruptive rocks 
of this district are all of Post-Triassic age. They are 
divisible into two series (1) an alkali-felspar series, and (2) 
a basic series. The former is typically represented by the 
so-called trachyte or syenite of the Gib-Rock, (allied to 
the rocks bostonite or nordmarkite, ‘monzonose’ of the new 
American petrological classification) and of Mount Jellore. 
The latter rock contains an interesting blue amphibole 
allied to arfivedsonite, but having special physical properties 
notably very strong absorption, which distinguish it from 
that mineral. The latter series (basic series) comprises in 
