lOO ROCKS USED IN THE MANUFACTURE OF TRONATTAS. 



The average figures, based on the examination of , 

 such a large number as 5,000 specimens, conclusively 

 prove the preponderance of hornstone. We may say 

 almost eight out of every 10 tronattas are made of horn- 

 stone, and, in comparison to it, the use of the other 

 rocks is insignificant. Next to hornstone comes the 

 porcellanite, while the use of breccia and other rocks is 

 very limited. 



The figures obtained for these seven localities are 

 rather interesting, inasmuch as they seem to prove that 

 the selection of the rocks was influenced by local condi- 

 tions. In the neighbourhood of Hobart, wdiere horn- 

 stone is rather rare, while porcellanites and in particular 

 breccia are common, the last two rocks sliow a much 

 higher percentage than at any other place. There is no 

 outcrop of hornstone known to me near Hobart — cer- 

 tainly not one that has been used by the Aborigines. 

 The nearest quarries— Clark's Quarry, or Mount Com- 

 munication and Walker's Quarry, near Plentv. are 

 about 20 to 22 miles in a straight line. Johnstone s and 

 Nichols' Quarries are about 30 miles distant. Inless 

 we assume' that the Aborigines broke the stone at these 

 quarries and carried it to their camping grounds, near 

 Geilston and Old Beach— a view which is not very prob- 

 able—we must suppose that they collected the rough 

 stone locally in gravel deposits. The proportion m 

 which the different rocks occur in these deposits is there- 

 fore reflected in the above figures. Where quarries were 

 handv, at places like Mona Vale, Mount ^lorriston— 

 Trefusis, and Melton Mowbray, the hornstone was used 

 in preference to all other rocks. It seems, however, 

 remarkable that at Shene, but particularly at Maryvale, 



