XVII. ABSTRACT OF PROCEEDINGS. 



the appearance of one half of a biaxial elliptical pebble 

 which has been cut in two and polished on the sliced surface. 

 It has a diameter of 35 mm. each way and a depth of 15 mm. 

 The pebble has four or five concentric layers of chalcedony 

 forming an outer coating which is about 5 mm. thick. 



Mr. Harris states that the pebble is in its natural 

 condition and that it was found loose on the surface of the 

 ground and that he handled several specimens of the same 

 size and shape from the same locality, and saw others 

 further south, near Beelah. 



The polished surface h-as the characteristics of a wind 

 polished surface with minor dimples, pits and grooves as 

 one might expect, and the edges of the " polished " area 

 are quite sharp. 



The only feasible explanation that could be offered as 

 to the origin of a number of pebbles of this shape is that it 

 formed portion of a conglomerate which had been sheared 

 80 as to cut through the pebble and that the sheared surface 

 had been subjected to wind erosion following on which the 

 pebble had been weathered out of its matrix. This ex- 

 planation might hold for an isolated pebble but cannot be 

 offered as the cause of frequent specimens of a similar shape 

 in different localities. 



Professor H. J. Priestlej', M.A., delivered a lecture 

 entitled " The Einstein Theory." At its conclusion a vote of 

 thanks was accorded the lecturer on the motion of Pro- 

 fessor Richards and Dr. Shirley, supported by the President 

 and Mr. Longman. 



Abstract of Proceedings, October 25th, 1920. 



The Ordinary Monthly Meeting of the Royal Society 

 was held in the Geology Lecture Theatre of the University, 

 at 8 p.m., on the 25th October, 1920. 



The President, Mr. F. B. Smith, B.Sc, F.I.C., in the 

 chair. 



His Excellenc}^ the Lieutenant-Governor, the Hon. 

 Wm. Lennon, Mrs. Lennon, Miss Lennon, and Captain 

 Plant, A.D.C., were among the visitors. 



