AUSTRALIAN GLACIATIONS 195 
clay sometimes passes into a coarse, angular grit in irregular 
masses; or includes sandstones, slates, and thin gritty limestones. 
The included stones are of the nature of erratics, being foreign 
to the localities in which they occur. They exhibit a great variety 
of types, such as granites, gneisses, and other granitoid rocks, 
Fic. 1.—Cambrian glacial til] (showing erratics of granite, gneiss, quartzite, etc.). 
Sturt Valley, S. Aus. J. Greenlees, photo. 
quartzites, porphyrites, schists, etc., some of which cannot be 
referred to any locality within the limits of South Australia (see 
Fig. 1). 
The very close resemblance which this ancient till bears to ice 
deposits of a recent date is at once recognized by the experienced 
observer, but the glacial origin of the beds was not taken as proved 
