vol. 69.] petrology op the kalgooelie goldfield. 677 



Discussion. 



Dr. J. V. Elsden said that the Author had made a valuable 

 contribution, both to practical and to theoretical geology. From 

 the practical standpoint, the speaker Avould like to know more 

 regarding the distribution and origin of the gold and the relation 

 of the auriferous veins to the quartz-dolerites. From the theoretical 

 point of view, the evidence of magmatic differentiation, adduced in 

 the paper, appeared to be of an especially interesting character. 

 With regard to the extensive albitization of the rocks, this was a 

 phenomenon to which petrologists were now giving much attention, 

 and the Author's observations would be widely appreciated. 



Q. J. G. S. No. 276. 2 x 



