40 Proceedings of the Royal Society of Victoria. 



the surface ; at Springfield in a bed of quartz wash six inches 

 thick, overlaid by two feet of alluvium, the whole resting upon 

 granite; in stanniferous drift at Norfolk Range; Camden Plain; 

 Mount Barrow in auriferous wash ; and at Lisle in auriferous 

 wash. We have one in the Technological Museum labelled from 

 Back Creek, and Clarke records one from Supply Rivulet, River 

 Tamar. No doubt obsidianites have been found in many other 

 parts of the colonies, and the foregoing is not by any means a 

 complete list, but it is as complete as I can make it from records 

 and personal information. It is however, I think, quite sufficient 

 to convince us that they occur all over the continent, and that 

 they are not restricted to any particular localities, also, owing to 

 their undeniable similarity of form and physical characteristics, 

 that they are invariably products of a like nature and have a 

 common origin. The two theories put forward to account for 

 the phenomena are : — First, that they are terrestrial volcanic 

 products ; second, that they are non-terrestrial products or 

 aerolites. It is generally agi-eed that if of terrestrial origin they 

 are primary volcanic products and are not due to concretionary 

 action in either eruptive or sedimentary rocks. If non-terrestrial, 

 then we can only conclude that they have been derived from 

 celestial bodies which are almost, if not quite, identical with 

 some of our volcanic rocks. To account for their widespread 

 distribution under the first hypothesis various agents are suggested, 

 and in order to deal with this point we will assume that they are 

 products of that nature. Four explanations are ofl'ered to account 

 for their distribution, viz.: — By rivers or creeks, by ice, by 

 means of the aborigines, and by the agency of the wind. 



Obsidianites occur both on the surface and in the alluvium, 

 and therefore, to a certain extent, there may have been a 

 distribution of water. With regard to the latter occurrence, I 

 have not been able to obtain any authentic information as to the 

 nature of these drifts, eJfcept that they are mostly shallow, and 

 that the presence of obsidianites in deep leads, although reported, 

 has not been verified. The specimens examined, which are said 

 to come from the drifts, are not in any way water-worn, and 

 Mr. George W. Card infoi'ms me that those found in the alluvial 

 of the Uralla showed no signs of attrition, their preservation 

 being pt^rfect. It seems probable that tliis feature is really 



