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gical character of the country, describes the superficial deposits which 

 he divides into — 



1. The unstratified drift or boulder formation. This, the lower 

 of the two superficial deposits, is characterised by the circumstance, 

 that most of the materials have been derived from the rocks on which 

 they now rest, or those in the vicinity. The fragments are angular, 

 and altogether devoid of any regular ari'angement. This unstratified 

 drift, however, does contain boulders from distant localities, which ' 

 may generally be traced. The appearances indicate that the mate- 

 rials have been transported from the noi'thward, and also, to a less 

 extent, from the southward, and, indeed, in various directions. 



Polished and sci'atched surfaces have been observed only in a few 

 localities ; but do not indicate a uniform direction, 



2. Stratified sand and gravel. This deposit generally rests on 

 the former. Sections were exhibited shewing this in two localities. 

 The pebbles of this gravel are comparatively small. It often forms 

 mounds of singularly regular form, resembling works of art. 



After minutely describing various localities, the author proceeds 

 to say that the facts indicate more than one cause of change. 1st, He is 

 disposed to consider the contour of the surface on which these depo- 

 sits rest as the result of powerful submarine currents, occurring pro- 

 bably during the gradual rise of the land. 2d, He considers the un- 

 associated state of the unstratified drift, and the small amount of at- 

 trition it has undergone as proofs of subaerial disintegration, possibly 

 effected by the frost and thaws of an extreme climate. 3d, The 

 great confusion of the fragments, and the presence of foreign boulders 

 indicates, he thinks, a subsequent period of submergence, and the 

 agency of icebergs, transporting these boulders in various directions. 

 Lastly, the mounds and ridges of stratified gravel may have been 

 formed during this period of submergence, or during the gradual rise 

 of the land. 



The agencies which have produced these deposits have played a 

 very important part in preparing the surface of the country for agri- 

 cultural operations ; and this is possibly one of the principal uses 

 which these deposits have been intended to serve. 



3. On certain Anomalous Deviations of the Transit Instru- 

 ment at the Royal Observatory. By Professor C. P. 

 Smyth. 

 Professor Henderson had found a connection between the changes 

 in the level of the transit axis and the readings of a thermometer 



