The manufacture of the tero-watta

Recent investigations have proved that the aborigines obtained the siliceous rocks used in the manufacture of their stone implements from two sources, viz.
1) From certain localities where such kinds of rocks occur in situ 2) From the gravel deposits of pleistocene and modern age, in the shape of waterworn boulders.
The former localities have very aptly been termed "native quarries," but it appears that, though these quarries were extensively worked, the material obtained from this source was not of the same importance as that obtained from the gravel beds.
The total of tero-watta made from locally occurring rock, therefore, does not exceed 14 or 15 per cent.
We, therefore, see that at the outside 15 per cent, of the tero watta were manufactured from rock obtained in quarries, while 85 per cent, were manufactured from rocks otherwise obtained.
Now, how were the tero-watta manufactured? The answer to this question is more difficult than it appears, and we will first see whether the historical accounts help to solve the problem.
In Conclusion The raw material required for the manufacture of tero-watta was for the greater part obtained in the shape of water-worn pebbles from the gravel beds, for the smaller part from so-called quarries.
It was also concluded that the parent block was broken by means of a hammer-stone.
Includes plates.