512 Geological Society. . . .. 
water (which is possible, but extremely improbable), we shall not 
know which of these two contains most matter; and in the present 
state of chemical science it is simply idle to pretend to compare the 
quantities of matter in two things of different chemical nature. 
We fail to see why a gramme should be called a ‘‘ mass-gramme,” 
and it is certainly not “ the quantity of matter contained in a cubic 
centimetre of distilled: water at the temperature and pressure at 
which water has its greatest density.” 
Until these and similar errors are corrected no competent teacher 
will consent to employ this production as a textbook. 
LIX. Proceedings of Learned Societies. 
GEOLOGICAL SOCIETY. 
{Continued from p. 393. | 
April 29, 1885.—Prof. T. G. Bonney, D.Sc., LL.D., F.B.S., 
President, in the Chair. 
(RES following communications were read :— 
1. On the Structure of the Ambulacra of some Fossil Genera 
and Species of Regular Echinoidea.” By Prof. P. Martin Duncan, 
M.B. (Lond.), F.R.S., V.P. Linn. Soe., F.G.S. 
2. “The Glacial Period in Australia.” By R. von Lendenfeld, 
Ph.D. Communicated by W. T. Blanford, LL.D., F.R.S., Sec. GS. 
Although several previous writers have suggested that boulders 
and gravels found in different parts of Australia are of glacial origin, 
the evidence is vague, and no clear proof of glaciation has been 
brought forward. During a recent ascent of the highest ranges in 
Australia, parts of the Australian Alps, the author succeeded in 
discovering a peak which he: named Mount Clarke, 7256 feet high, 
and in finding traces of glaciation in the form of roches moutonnées 
throughout an area of about 100 square miles. The best-preserved 
of the ice-worn surfaces were found in a valley named by the author 
the Wilkinson Valley, running from N.E. to 8. W., immediately south 
of Miller’s Peak and the Abbot Range. No traces of ice-action 
were found at less than 5800 feet above the sea. 
The rocks showing ice-action are all granitic, and the fact that 
the surfaces have been polished by glaciers is said to be proved by 
the great size of such surfaces, by their occurrence on spurs and 
projecting points, by many of them being worn down to the same 
general level, and by their not coinciding in direction with the joints 
that traverse the rock. 
In conclusion the author briefly compared the evidence of glacial 
action in Australia with that in New Zealand. 
3. ‘* The Physical Conditions involved in the Injection, Extrusion, 
and Cooling of Igneous Matter.” By H. J. Johnston-Lavis, M.D., 
F.G.8., &e. . 
The great disproportion between the displays of volcanic activity 
