BY A.. N. LEWIS, M.C. 2L 



a mile in length, and reached to about the 3,000 feet level. 



It must be borne in mind that the erosion of the var- 

 ious creeks working up their valleys may have destroyed 

 traces of ice action lower down than the altitudes mention- 

 ed, but this cannot have happened to any great extent, as 

 the erosion has had little effect on other glacial remains 

 in other parts equally exposed, so short has been the time 

 since the disappearance of these glaciers. 



Up to the present, there have been found in this part 

 of Tasmania no indications calculatea to throw any light 

 on the age of this glacial period, but the remains are of 

 most recent age, and evidences elsewhere in Tasmania 

 place the occurrence in the Pleistocene period. The glaciers 

 in the National Park were contemporaneous with those 

 elsewhere, and strong evidence to the contrary would have 

 to be deduced to alter the settled opinion that these glaciers 

 belong to the Pleistocene. 



Unfortunately, the entire area affected by this agency 

 is of diabase. This makes it impossibi3 to observe different 

 kinds of rock in the moraines or to guess where the materials 

 came from. Also the diabase weathers too rapidly to re- 

 tain any traca of stri£e. This is also the case with very 

 much harder rocks. "It must be bcrne in mind that weather- 

 "ing agencies have been at v/ork so long and disintegrational 

 "forces so active, that all positive traces on the rock sur- 

 "faces would have been destroyed in the case of such rock 

 "as granite." (Waterhouse, 191G.) "The Conglomerate" 

 (West Coast Series Conglomerates of the Cambrian system, 

 one of the hardest of rocks) "does not possess the requisite 

 "texture for the preservation of the striations which almost 

 "invariably have been effaced by exposure to the weather." 

 (Reid, 1918.) Perhaps glaciated pebbles that have been pro- 

 tected from weathering processes by clay or sand may yet 

 be found in the National Park with signs of striations. 



Time and weather have prevented a complete explora- 

 tion of the National Park, and other regions of glaciation 

 may yet be found, especially north of Mt. Field East, and 

 between the valleys of the Broad River and Bunyip Creek, 

 and even over the shoulder between Mt. Field West and 

 the Florentine Peaks. There is still ample scope for the 

 enthusiast. The author can only hope that this paper may 

 be of some assistance. 



