1866.] the Western Himalaya and Afghan Mountains. 103 
of albite sometimes become loosened in their matrices, and, falling 
out, leave angular cavities on the face of the rock. The rock, 
when fresh and well crystallized, is however very hard: some 
varieties appear to crumble much more quickly and completely than 
others. 
Ii.—The grains of magnetic iron ore and the gold I have not seen 
in the porphyry,* but they are found in the sands which, I will now 
endeavour to prove, have been formed by the decomposition of these 
volcanic rocks. 
Gold is washed in most of the rivers which traverse the miocene 
sandstones and conglomerates of the sub-Himalaya, and is always 
found associated with grains of magnetic iron ore. Let us examine 
one of the districts where the washings are, I believe, most abundant, 
the banks of the Soane river, in the districts of Jheelum and 
Rawul Pindee, especially near the villages of Pindeh Geb, Kothair 
and Mukud. Let us therefore go to Rawul Pindee and travel towards 
the $8. W. along the road to Kalabagh. We find that this dreary 
road, about 120 miles long, crosses obliquely from the N. N. H. to the 
S. S. W. the great plateau of miocene sandstone, conglomerate 
and clay (Sect. G.). 
There is a thick bed of miocene sandstone and conglomerate, 
above 2,000 feet thick, which might be called the upper miocene 
formation of the Sub-Himalaya (contemporary of the Sewalik hills 
and containing the same Mammalian fossils), whilst the sandstone 
and shales of Murree and adjacent hills, about 5,000 feet thick and 
without fossils, might be regarded as the inferior miocene. These 
two divisions of the miocene are not exactly one on the top of 
the other, but rather the upper bed thinning towards the north, 
covers in the southern edge of the lower bed in an intricated 
* A similar granitoid porphyry exists in Portugal, in the hills near Cintra 
about five leagues from Lisbon. It is there very variable in appearance and 
consistency, and is generally made up of large grains of felspar and of quartz, 
and of large plates of mica. It contains grains of magnetic iron ore, but I am 
not aware whether it contains the large twin crystals of felspars seen in the 
Kaj Nag porphyry. The Portugal rock is generally described by travellers as 
granite, but is considered by geologists as decidedly volcanic. It presents 
the character of crumbling easily after a certain amount of exposure, 
