Mineralogy and Geology. 121 
3. On the Physical Geology of the ——— ee Captain Ricnarp 
Sreacuey, F.R.S., F.G.8., (Jour. Geol. Soc., 49.)—The author 
basis in a previous communication to the Sockety.* described the ge- 
Attention was first directed to some of the more a points of 
the physical structure of the great mountain mass, of which the Hima- 
laya forms a portion. Among these were especially noticed :—Ist. The 
general form of the section of the mass, which shows that ar Hime 
the summit of which forms the table-land of Tibet, while tha northern 
slope is a mountainous region, marked on our maps as the Kone , simi- 
lar to the Himalaya, and terminating in the great plains of Central Asia. 
« The parallelism to one an other, and to the outer e ‘the moun- 
a tain area, of the great ridges or lines of elevation ; as ne great valleys or 
li . . . e 
to their mineral character 
and geological age. 3d. The ar sane he drainage, in accord- 
ance with which the crests of the. ipo Sod southern slopes of the 
Rape mass form two main lines of water-shed, proposed to be termed 
he.‘ Turkish. and tm Water- sbeday” to the north and south of which, 
a 
alone, the Brahmaputra and the Indus, which are discharged from the 
Mountains at two distant points, at opposite ends of the chain. 4th. The 
Constancy maintained for great distances along the length of the agp 
both in the geological structure, and in the elevations to whic 
Mountains rise; which last character is <r as ‘by the sf 
perfect horizontality of some of the most elevated stra ified ieee by 
the ex grist ge small slope of the main drainage- channels of the 
table-land, and wikia the general similarity of the altitudes even “ng 
to the view which attributes elevations on the earth’s sur: c 
aubsidenses of the iawes parts, and having stated reasons rs be evng 
that in the present instance the elevation was real, a review was ta 
that had taken = 
Hence it was eh that the agent of elevation was probably a de- 
velopment of elastic vapors, a s has been cons Mr. Hopkins to 
4a be likely in a general point of view. ‘The probability of this in the 
~ % * Quart. Journ. Geol. Soc., vol. vii, p. 292 
> Series, Vol. XX, No. 58.—July, 1855. oP 
