Further Note OH Glacial Deposits, Bacchus Marsh. 141 



(4). A somewhat clayey unstratified deposit, which does 

 not seem to contain so many stones as the bottom 

 deposit. 



(5). Shales and fine-grained well stratified sandstones. 



A section exposed on the Lerderderg River, about two miles 

 above Darley, shows unstratified clay containing irregular and 

 lenticular bands of hard coarse sandstone, associated with 

 well stratified fine glacial clays. Striated stones and boulders are 

 \ery abundant through this, and are, as a rule, exceptionally well 

 scored. One of these boulders, a hard blue slate, is five feet six 

 inches long, three feet six inches broad, and a depth of two feet 

 is exposed ; the surface is well scored in a longitudinal direction, 

 though cross strise occur also. Several other boulders at this 

 section are over two feet in diameter. Though stones occur in 

 the stratified parts yet they are not nearly so abundant as in the 

 unstratified. It is worth mentioning, as illustrating the tough 

 and tenacious nature of the unstratified till, that a farmer 

 resident in the locality, in course of conversation with us, 

 remarked that he had never come across such an unsatisfactory 

 material to work. In constructing a race he had occasion to pass 

 through some of it, which proved very obstinate to the ordinary 

 methods of excavation. Blasting had hai-dly any efiect, and he 

 said the only way to deal with it was to knock it away bit by bit 

 with a hammer and a gad. 



We traced the till on to the crest of a spur of the Lerderderg 

 Ranges at a height of about 1000 feet above sea-level (aneroid 

 reading). At one place on the flanks of these ranges, where w^e 

 could actually see the junction of the till and the Silurian, we 

 found the latter well scored and grooved. In the striated rock 

 surfaces described in our last paper, the strise and grooves were 

 N. and S., being parallel to the strike of the rocks. In this case 

 the direction of the strise and grooves is W. 10° N. and E. 10° S., 

 almost at right angles to the strike. In the former case the 

 grooving and moulding was more marked and may be compared 

 to grooves made by a gouge working with the grain of a piece of 

 wood, while in the latter instance the appearance is somewhat 

 similar to that made by a blunt gouge woi'king across the grain 



