49, On Local Attraction. [No, 1, 
From the above letter it will be seen, that I come to the conclusion 
that the earth’s crust below the mountains is somewhat less dense than 
below the plains; and still less than below the ocean-bed. Mr. Airy 
(Plul. Trans. for 1854, p. 101) came to the former part of this conclu- 
sion. But his argument requires that the crust should be thin—and 
so thin as to be influenced for its position by the principles of floata- 
tion. But Mr. Hopkins’ and Prof. W. Thomson’s results show that 
the crust cannot be thin. Moreover Mr. Airy’s line of reasoning does 
not lead to the latter part of the result, in that the crust is more dense 
below the ocean-bed. For these reasons I have not alluded to Mr. 
Airy’s hypothesis in my Paper. The argument therein explains both 
these phenomena without requiring that the crust should be thin, but 
rather the contrary. 

Notes to accompany a Geological map and section of the Lowa Ghur or 
Sheen Ghur range in the district of Bunnoo, Punjab ; with analyses 
of the Lignites—By Ausert M. Vercuere, Ese., M. D. 
[Received 10th June, 1864. ] 
Description of the Section, Pl. ITI. 
1. Hillocks or morraines formed by the pebbles and boulders of 
miocene conglomerates and sandstones which have been removed by 
the effect of the rains: the sand is carried away to the plain, but the 
boulders and pebbles are left behind and form a morraine. The 
stones have arranged themselves in layers resting against the miocene 
beds, with an inclination towards the plain (W) of 20°. 
2. Miocene (?) sandstone, very friable, grey or rather salt and 
pepper ; calcareous and often so soft that it can be crumbled in the 
hand. It contains boulders and pebbles, well rounded and worn, 
generally arranged in bands. It is these boulders and pebbles which 
form No. 1, as No. 2 is being destroyed. The pebbles and boulders 
are greenstone, quartzite, quartzose porphyry, gypsose agglomerate, 
carboniferous and nummulitic limestone, etc. 
3. Similar to 2, but a little harder, and contains occasionally bands 
of slate in a state of disintegration. Carbonized wood found here, 
(seldom,) in an iron-stained sandstone. 

