Art. VIII. — Geological Notes on the Country betzveen 

 Strahan and Lake St. Clair, Tasmania. 



(With Map.) 



By GuAHAM Officer, B.Sc, Lewis Balfour, B.A., and 

 E. G. Hogg, M.A. 



[Read 14th June, 1894.] 



The following sketch is the outcome of observations collected 

 during a trip made by the authors in January of this year from 

 Strahan to Lake St. Clair along the OA^erland track. 



The first thing of interest, that does not seem to have been 

 recorded as yet, is the occurrence about a mile from Strahan 

 along the track of a deposit which bears a striking similarity to 

 the glacial drift in Victoria. It consists of an unstratified or 

 faintly stratified clay, of great hardness in places, and through 

 which stones and boulders are irregulaidy scattered. One of 

 these boulders was two feet in diameter, and several bore stria*. 

 In places the clay has a peculiar pinkish-purple colour that is 

 very characteristic of the glacial beds near Bacchus Mai'sh. As a 

 similar deposit occurs on Mount Tyndall and also on Mount 

 Sedgwick, not very far distant, it is not improbable that the two 

 are identical. We did not observe a direct junction with tlio 

 Silurian rocks which appear here and occur all the way to the 

 great central plateau. 



Mounts Lyell and Owen form part of the West Coast Range, 

 and are at a distance of some thirty miles from Strahan by the 

 track. These two mountains run approximately parallel to each 

 other in an E. and W. direction, being separated by the wide, 

 open Linda Valley. At their westerly extremity they are con- 

 nected by a narrow saddle, which rises to a height of about L'jOO 

 feet above sea level; from this end arises the Linda Creek, which, 

 after being joined by its tributaries, runs due east down the 

 valley for about four miles, when it flows into the King River. 

 Towards its lower end the valley narrows rapidly as the eastern 

 spurs of Mounts Owen and Lyell approach each other. 



