15 



FIG 1. (i>) 



PIECE OF COLUMNAR DIABAS : Gcilston. 



This prototype of every human tool is nothing else 

 but a piece of columnar Diabas, which has been picked up 

 at such places where the Diabas on cooling from its molten 

 state, instead of contracting into huge columns, produced 

 smaller ones, which were from their shape eminently suit- 

 able as choppers. Had the rock been less brittle, these 

 natural pieces of Diabas would have been very efficient 

 tools, but their extreme brittleness made them very unsuit- 

 able even for the limited wants of the Tasmanian Abori- 

 gines. Space does not pemiit to dwell longer on this type, 

 which is full of the deepest interest. I shall have, pro- 

 bably, an opportunity of dealing with this subject in a 

 separate paper. 



B. WATERWORN PEBBLES. 



Next to the pieces of columnar Diabas, ordinary water- 

 worn pebbles represent the lowest type of implements. 

 Any flat pebble might be used, provided it had a fairly 

 shai-p edge, which made it suitable as a chopping tool 

 without previous trimming. A very characteristic specimen 

 is shown in the following figure. 



FIG. 2. 



Ba. WATERWORN, FLAT PEBBLE USED A!S 



CHOPPER. Shene (Pontville). 



Another more frequent type are pebbles which, at the 

 butt end, still preserve their original surface, while the 

 other end is more or less flaked. It is difficult to say 

 whether these traces of wear and tear are solely due to 

 ■use, or to intentional flaking, the result will in both cases 

 be practically the same, though it is evident that Doth 

 represent two different classes of implements, l^he former 

 are Eolithes, the latter are Archaeolithes, which were never 

 finished, and rejected. 



The most frequent types of group B, which can also 

 be considered as the lowest Archseolithic type, are flakes 

 of pebbles still preserving their original crust as tne Ju- 

 dical face, but being always characterised by a Pollical 

 face. In thickness, as well as as in shape, these flakes vary 

 considerably, and it is unquestionable that they have been 

 struck off from a larger block. Sir John Evans calls this 

 type "external flakes." Some of the thinner ones, whicli 



(•2) All figures considerably reduced in size. 



