Records of the Geologicul Surrey of hulia. 
[vol. VIII. 
74 
be an original great bank of sand witli the muddy oyster bed alongside of it. Nothing 
short of an artificial out across the rocks could finally dispose of all these objections; but 
certainly the first and most probable explanation is that of original denudation-unconformity. 
The incompatibility of the even approximate contemporaneity of such rocks as these now 
are, indefinitely increases this probability. 
The oyster bed and its associates are characteristic representatives of the Bagh beds 
of this region. All the petrographies! characters of the Gatta rock point to its being a re¬ 
presentative of some member of the Mahadeva series of Central India. I failed, owing to the 
Ituli festival, to get to the larger area of similar rocks about Kdtkot. I suspect the great 
quarries opened there for the works on the ghat are in the same rock as at Gatta. 
Inference as to coal. 
The observation I have just explained has a very direct hearing upon the object of my 
trip westward—the possible extension of the coal-fields. It has 
not been sufficiently noted that the. resemblance of the massive 
sandstones of the lower Narbada valley, especially in the Deva valley close to the alluvial 
plains of Broach, as repeatedly observed by Mr. Blanford, is a permanent character, and 
would hold true whatever geological rearrangement the original Mahadeva group might 
undergo; also, that the connecting of those rocks with the overlying cretaceous beds is 
given with great doubt by Mr. Blanford, more because be bad not detected any break be¬ 
tween them, than from any dependence upon their apparent confomiability. This missing 
link of evidence has now been found, and Mr. Blanford’s original conjecture confirmed. It 
is certain that at least some of the rocks in tlie Western Narbada area provisionally placed 
with the cretaceous formation are not only lithologically like the Mahadevas, but are strati- 
graphieally related to the cretaceous beds just as the Mahadevas of the eastern area arc to 
the Lametas. There is scarcely much risk in supposing that the sandstones of the Deva 
valley arc the same as the Gatta rock; and if so, the position of the Mahadevas as now 
understood would give a new significance to the fact, suggesting very directly the possible 
or even probable occurrence of the eoal-measnres. It is not for a moment supposed that 
there are outcrops of the Damudas in the Deva valley ; and no probable guess can be 
made as to the depth at which they are likely to lie; 2,000 is as likely as 500 feet. 
The prospect would include the neighbourhood of Burwai. No doubt the rock at Gatta 
rests immediately on metamorphics ; but there are like overlaps of the Mahadevas in their 
typical area. The Katkot outlier is also very likely to he shallow. I saw, however, at the 
viaduct a quantity of cut stone of the same description from a place near Akhund, to the 
south-east. It is possible this may he the lip of the basin from which Gatta is an overlap, 
ami that coal may be within reach. Of its great value in such a position I need not remark. 
1 had sent my camp by forced marches to Banker! railway station, and had no means of 
going about, having already overtaxed the hospitality of the local officers. 
A general consideration of the case does not discourage those suggestions. The great 
Satpura basin almost certainly had its outlet to the west. Its uppermost strata spread out 
to the east over the gneiss at the watershed of the peninsula. It is not unreasonable to 
suppose that to the west as to the east of India an expansion of the lower coal-bearing 
groups took place towards the sea-board, and that the Bengal fields may have underground 
equivalents in the region of the lower Narbada. 
IV.— The Shapue Coal field. 
In the event of failure to find coal, and in sufficient quantity, on the north side of the 
Position Satpura basin, the alternative will he to take up the most accessi¬ 
ble position on the southern outcrop of the measures. In anti¬ 
cipation of this necessity, a survey has been made of that portion of the ground where 
