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The writer hopes that this note may lead to some future systematic examination by experienced geologists, who may decide whether the conditions are sufficiently promising for



The specimens sent are felspathic sandstones, possibly of the Dharwar period. I only suggest this as nothing definite can be said regarding the age of the rock unless the adjoining rocks are examined.

The friability is due to the removal of ielspars owing to weathering, leaving an aggregate of interlocking quartz grains held together (loosely) by secondary growth of quartz. One side of the rock is more so than the other.

The red coatings are due to iron-oxide and absence of organic vegetable matter.

The black coating also contains iron-oxide but some organic vegetable matter is also present in the coating. Owing to the hardness of iron-oxide and the presence of organic gelatinous matter which has made the surface of the black coatings very greasy, the rock is and this accounts capable of resisting weathering to some extent for the preservation of the drawings.

Traces of lime are present in the specimen but no manganese. The colour of the coating varies according to the proportion of vegetable matter in it.

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