DISCOVERY OF GLACIATED BOULDERS. 155 



scratched and somewhat polished, which he considered to be of 

 undoubted glacial origin. 1 There can be no question now in view 

 of a later discovery this year that the markings on this pebble 

 were really of glacial origin, though taken by themselves at the 

 time they appeared to me, when the pebble was shown to me by 

 Mr. Oldham, to be probable rather than positive evidence of con- 

 temporaneous ice action. 



In 1887, in a paper read before the Geological Society of 

 London, 2 I recorded the occurrence of numerous erractics in the 

 Permo-Carboniferous Upper Marine Beds between Grasstree and 

 Liddell, N. S. Wales. Many of these boulders were faintly 

 scratched on the top, bottom and sides, but no grooves were visible. 

 The markings on these boulders recalled the appearance of the 

 surfaces of boulders in the redistributed boulder-clays of Glamor- 

 ganshire in South Wales. I considered them to be of probable 

 glacial origin, but the evidence was considered inconclusive by 

 several members of the Geological Society of London who examined 

 the boulders, and it must be admitted that the striae were very 

 faint. 



In 1895 3 I exhibited at the Australasian Association Meeting 

 in Brisbane a photograph taken by me of a block of granite 

 measuring two feet three inches high by one foot three inches by 

 at least three feet three inches long, bedded in the Upper Marine 

 Permo-Carboniferous Rocks near the end of the Railway Cutting 

 nearest Black Creek, west of Branxton Railway Station. The 

 block is bedded on its edge, and the stratum on which it rests is 

 indented, while the stratum above does not partake at all of the 

 indentation, showing that the disturbance of the bed on which 

 the boulder rests was due to the impact of the boulder as it fell 



1 Records Geol. Survey of India, Vol. xix., p.t i., p. 44. 



2 Q.J.G.S., Vol. xliii., pp. 190-196.— "Evidence of glacial action in 

 the Carboniferous and Hawkesbury Series, N. S. Wales." 



3 Proc. Austr. Ass. Adv. Sci., Vol. vi., Brisbane — President's Address, 

 Section C, p. 70. 



