Vol. 60. THE GLACIAL GEOLOGI OF TASMANIA. 51 



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erratic ; and although the hole was 20 feet deep, it did not reach 

 the bottom of the clay. 



Associated with the conglomerate-boulders are others of various 

 igneous rocks, belonging to the series of felsites. I pulled three 

 small boulders out of the clay exposed on the cutting for a culvert, 

 close to the biggest erratic ; two of the three boulders had glacial 

 scratches. The glacial clay was soft, though tough ; it had the 

 lithological characters of a recent, and not of a Carboniferous glacial 

 deposit. Moreover, the northern face of Mount Black (altitude 

 about 3500 feet), the nearest conspicuous mountain, appears con- 

 spicuously mo u tonne e, affording further proof of recent glacial 

 action in this part of Tasmania. 



Mr. Stirling kindly invited me to ride on the locomotive from 

 Farrell to Zeehan, and thus I had a better view of the cuttings 

 than I could have got from the railway-carriage. I was thus able 

 to notice that the glacial deposits occurred at intervals along the 

 line from Farrell to near Zeehan. As the train sometimes went 

 slowly up the steep grades, I had a fair view of the sections 

 exposed. The sections along the ascent from the bridge over the 

 Pieman River, up its left bank, show a typical boulder-clay, with 

 boulders 2 feet or more in length, embedded in a line clay. The 

 shape of the boulders suggested ice-wearing, and they rest in places 

 upon the worn surface of the schists. Farther along the line there 

 are some finely-bedded clays, covered by a layer of boulder-clay. 

 Between Bobadill Creek and Chasm Creek are some more bedded 

 clays resting upon clay and slate, and overlain by boulder-clay. 

 The bridge over the Pieman is 400 feet above sea-level, while the 

 railway-bridge over its tributary the Ring River is at a slightly 

 lower level : and in both cases the glacial beds occur almost at the 

 level of the bridges. About Rosebery, at the level of 510 feet above 

 the sea, there are also some good exposures of boulder-clay ; the last 

 of the boulder-clays, however, were left some time before reaching 

 Zeehan. The boulder-clavs in this area seem to occur in an irregular 

 sheet, descending in the deepest pre-glacial valleys to but little 

 over 400 feet above the level of the sea. 



The glacial deposits of Farrell, Rosebery, and Dundas may be 

 assigned to the action of a Pleistocene glacier, which flowed north- 

 westward from the ice- sheet of the Central Plateau. Moreover, 

 the erratics found by Sprent in the Mackintosh Valley, at a locality 

 only some 6 miles from Farrell, may be safely attributed to the 

 Pleistocene, and not to the Carboniferous glaciation. 



The railway-line from Zeehan to Strahan, on Macquarie Harbour, 

 passes through a series of cuttings in coarse boulder-deposits ; they 

 extend along the line for 2 or 3 miles, on the northern side of 

 the Henry River, between Mallana and Eden. They range in 

 altitude from about 50 to 350 feet above sea-level. 



For an opportunity of examining one of these sections I am 

 indebted to the courtesy of Mr. Parry, the station-master at 

 Zeehan, who kindly stopped the train for me. A four-minutes' 



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