PART 8. 
Theobald: Occurrence of erratics in the Potwar. 
143 
smallei blocks in the same neighbourhood. An equally large block occurs close to Suriali six 
miles to the south-west, whilst six miles north-west of this last occurs another not quite so large. 
These two last blocks are the most divergent, being five miles apart, and between them the 
great central course of blocks seems to pass. Below Shah Maliomedwalla, erratic blocks, mostly 
of gneiss, are numerous, but above that village the Soan has engulphed them, or the blown 
sand in the low land south of the river has covered them up. Enough, however, remains 
clearly to establish the fact of their being two trains of erratic blocks in the Potwar, many of 
which blocks range from 20 to 40 feet in girth, and some of which at all events are im¬ 
pacted in a thin-bedded silt. These two trains of blocks are twenty miles apart, and their 
course very nearly at right angles to that of the Indus, but coincident with that of its main 
feeders in the area in question at the present day (the Soan, etc.). 
My colleague, Mr. Wynne, has also found numerous erratics, with an excellent sketch of 
some of which he has kindly supplied me, but beyond a mere announcement of this corrobora¬ 
tive fact I need not now go. The discovery of one or more pieces of the dark Trans-Indus 
gypsum has, I believe, led my colleague to entertain a suspicion that these erratics have tra¬ 
velled from the west; but this I think must be viewed with the utmost caution, as whether 
we regard the erratics as borno by floating ice or not, it is hard to concievo that any train 
of blocks coming from the west would pursue (as I have shown the Potwar erratics to do) 
a course to the east-north-east. 
The above simple exposition of the few facts bearing on this interesting question, 
gathered by me in the course of my last season’s work, must suffice for the present, as till we 
lmow more of the direction whence these Potwar erratics descended, speculation on the subject 
would be vain. One thing, however, I regard as established,—namely, that whilst glaciers 
were ploughing their way down the great Himalayan rivers and valleys to within 2,000 feet 
or so of the sea, the Potwar was one great lake, with an exit probably near Kakbfigh as now, 
and into which lake glaciers descended freighted with the debris of the hills of Hazara 
and Kashmir. 
W. THEOBALD. 
Dharmsala, June 1877. 
On recent Coal explorations in the Darjiling Distbict, by F. R. Mallet, F.G.S., 
Geological Survey of India. 
At the time when the construction of the Northern Bengal Railway was commenced, the 
Government of Bengal, in view of the importance of obtaining, if possible, a supply of 
coal within a distance less great than that from the known coal-fields of Raniganj or 
Kaharbari, requested that an examination should be made into the mineral resources of the 
Darjiling hills, with reference more especially to coal. To this duty I was deputed during 
the cold weather of 1873-74. The results of my work are included in Part 1, Yol. XI, of 
the Memoirs of the Geological Survey. 
In that report it was shown that a narrow hand of Damuda rocks stretches from Panka- 
bari eastwards as far as Dalingkot, at an average distance of two or three miles from the base 
of the hills. The strata, however, have undergone great crushing and distortion, and are tilted 
up on edge, dipping generally at a high inclination . often vertically, and seldom at lower 
angles than 30° or 40°. Such disturbance is accompanied by great change in the 
lithological characters of the rocks, the sandstones and shales being frequently converted 
into quartzites and slates, respectively, while the coal has lost a large proportion of its 
