That work forms Part III of the _Manual of the Geology of India_.
7.

The soil of the valley of the Nerbudda, and that of the Nerbudda and Sagar territories generally, is formed for the most part of the detritus of trap-rocks that everywhere covered the sandstone of the Vindhya and Satpura ranges which run through these territories.

This basaltic detritus forms what is called the black cotton soil by the English, for what reason I know not.

[W.

H.S.] The reason is that cotton is very largely grown in the Nerbudda Valley, both on the black soil and other soils.