Preliminary note on the rocks used in the manufacture of the tronattas.

The observations here recorded are based on the examination of more than 5,000 specimens, all collected by myself chiefly in the southern and central parts of Tasmania.
If the metamorphic theory is correct, it stands to reason that there must be a considerable number of varieties of cherty rocks. A metamorphosed sandstone must be considerably different from a rock whose origin is a shale. But not only are the primary rocks widely different in chemical composition, but each kind, whether sandstone, shale, or anything else, varies considerably.
Whenever a collection of native stone implements is made in the island, and such collection be sorted afterwards, it will be found that two large groups can be distinguished at once: Volcanic rocks and Metamorphosed sedimentary rock of a highly siliceous nature.
The above investigation has conclusively proved that there is a great variety of rocks used in the manufacture of the tronatta. This variety of substances stands in a sharp contrast to the monotony of the material used in the manufacture of the European implements.
Variety of material and monotony of the same are the chief distinguishing feature of an otherwise undistinguisiiable collection of eolithes and archaeolithes from Tasmanian and Europe.