XXX ABSTRACT OF PROCEEDINGS. 



PAPER : 

 Mr. W. R. Browne gave an account of recent work on 

 Differentiation in Igneous Rocks. After a short sketch of 

 previous work, Mr. Browne described Dr. Bowen's work 

 and experiments, as a result of which the conclusion is 

 reached that the separation and sinking of crystals is the 

 principal factor in differentiation, though liquation may 

 also play a part. 



A discussion followed, Professor David, Mr. Ootton, Mr. 

 Tilley, Dr. Anderson, and the lecturer taking part. 



Monthly Meeting, 8th October, 1919. 

 Professor David in the Chair. 

 Ten members and four visitors were present. 



exhibits: 



1. Mining Museum: — Smaltite with scheelite, Oloncurry, 

 Queensland; erythrite, Oloncurry, Queensland; scheelite, 

 The VVaratah Mine, Hillgrove; molybdenite in intensely 

 folded crystals, Allies' Mine, Deepwater. 



2. Mr. W. T. Watkin Brown : — Eckmannite from Mrs* 

 Brown's Wolfram Mine, 30 miles S.E. of Pine Greek, 

 Northern Territory. 



3. Professor David: — Metallic meteorite (hexahedrite) 

 from Bingara; it is probable that this iron, the original 

 Bingara meteorite, and the Barraba meteorite are part of 

 the same fall. 



4. Mr. Alfred E. Stephen:— -Phosphatic rock from Mans- 

 field, Victoria. This aluminous phosphate has long been 

 known and is now being exploited commercially, it contains 

 up to 23 per cent, of phosphoric acid. 



5. Mr. W. R. Browne exhibited the following specimens 

 from Broken Hill: — Staurolite schist; cordierite — bearing 

 pegmatite and granulite; albite aplite replacing schist; 



