TBANSACTION* OF SECTION C. 537 



Addrndwu . 



Since tlie close of the meeting the followuig li&t of references to authoi'ities on 

 like or allied phenomena has heen prepared by Mr. W. Topley, F.G.S., Geological 

 Survey of England : — 



1795. J. Ilutton : ' Theory of the Earth,' vol. i. p. 467 (Arran). 

 1836. J. Phillips : ' Geology of Yorkshire,' Mountain Limestone District, p. 14 

 (Old lied C 'on glomerate, AV. Yorkshire). 



1844. [R. Ghamhers] : ' Chambers' Journal,' Nov. 25. 



1845. [Sir] W. 0. Trevelyan: 'Quart. Journ. Geol. Soc' vol. i. p, 147 



(Arbroath and Stonehaven). 

 1850. W. Stevenson: Ibid. vol. vi. p. 420 (Old Red, Lammermuirs). 



1856. [Sir] A. 0. Ramsay: Ibid. vol. xi. p^ 200 (New Red Conglomerate). 

 1855. J. Nicol: Ibid., p. 545 (Stonehaven). 



1857. A. Daubree: ' Comptes Rendus,' vol. xliv. p. 823 (Experiments). 

 1860. J. TyndaU : ' Glaciers of the Alps,' p. 404. 



1860. E. Hitchcock : ' Amer. Assoc. Sc. p. 156. 



1861. E. Hitchcock : ' Amer. Journ. Sc' vol. xxxi. p. 372. 



1861. H. J). Rogers : Ibid. vol. xxxi. p. 440. 



1862, E. Hitchcock : Sixth Ann. Rep. Maine Board of Agriculture (quoted 



in ' Quart. Journ. Science,' vol. i. p. 125, 1864). 

 1862. [Sir] A. C. Ramsay : ' Catalogue of Rock Specimens, Museum of 

 Geology, London,' 3rd ed. p. 11, Silurian, "Wales ; p. 60, Old Red ; 

 p. 116, New Red. 



1865. H. C. Sorby : ' Proc. Geol. and Polyt. Soc' West Riding of York- 



shire, p. 458. 



1866. J. Geikie : ' Quart. Journ. Geol. Soc' vol. xxii. p. 513 (Silurian, 



Ayrshire). 



1869. W. P. Blake : 'Amer. Assoc. Sc' vol. xviii. p. 199. 



1870. A. Geikie : ' Catalogue of Rock Specimens, Edinburgh Museum,' pp. 



51,55. 



1871. 'Memoirs of the Geological Survey of Scotland,' Sheet 15, pp. 



17, 21. 



1874. H. C. Sorby : ' Impressed Limestone Pebbles ' (Cardiff Nat. Soc.) 



1875. W. Molyneux : ' N. Staff. Field Club Papers ' for 1875, p. 103 (New 



Red, Trentham). 

 1879. A. Daubree : ' Etudes Synthetir^ues de Geologie Experimentale,' vol. i. 



p. 404 (Experiments). 

 1882. A. Geikie : ' Text Book of Geology,' p. 312. 



N.B.— In the publications of Sorby (1874), Daubrt5e (1879), and Geikie (1882), 

 references are given to authorities other than those noted above. 



2. On Features in Glacial MarJcivgs noticed on Sandstone Conglomernfes at 

 Skehnorlie and Aherfoil. By Professor James Thomson, LL.D., 

 F.RS. 



When glacial striation is met with on rock faces, it may often be a matter of 

 interest to find in which way along the direction of parallelism of the striie the 

 abrading or polishing ice must have advanced. Casual observers, unskilled in the 

 scrutiny of glacial phenomena, may sometimes too hastily assume, when they find 

 the lines of the striae inclined to the horizon, that the ice has been moving over the 

 striated rock-face or hill-side in the downhill direction of the striae. The direction 

 of the motion of the ice along the strite, however, cannot generally be safely inferred 

 from mere local configurations of the land ; and, in some cases, the configuration of 

 the laud, whether locally regarded or considered in wide scope, may afford no de- 

 cisive proof at all as to ■which way the ice has advanced along the stria). 



