TRANSACTIONS OF SECTION C. 631 



and 400 miles south of the Salt Range, and belongs to a gi'oup of beds supposed to 

 be Archaean, and known by the name of Malani. These rocks may occur nearer to 

 the Salt Range, but the intervening country is imperfectly known, and is much 

 covered with river alluvium and blown sand. 



The boulder exhibited measures 7^" x 6" x 3;^". It is subangular, the two 

 principal surfaces are plane, smooth, finely striated, opposite to each other, and 

 nearly but not quite parallel. Each of these surfaces is bevelled off on one edge 

 by a number of smaller facets, meeting the principal surface and each other at very 

 obtuse angles. Besides the larger plane surface there are on one side five 

 smaller smoothed facets, and on the other two, but one in each case is ill-marked, 

 the angle at which it meets the next siu'face being so obtuse as to be with difficulty 

 recognised. All the smoothed surfaces on one side are striated in the same direc- 

 tion ; those on the other side are striated similarly to each other, but diversely to 

 those on the opposite surface of the block. Those surfaces of the block that are 

 not smoothed are somewhat rounded. 



The bed from which the block was obtained is said to abound in similar 

 boulders, but they are not in general smoothed or striated. They are found in an 

 olive-coloured matrix of fine silt. The bed has been described by Mr. Wynne, 

 Dr. Waagen, and Mr. R. Oldham, and a general resume of its geological relations 

 was given in the ' Quart. Journ. Geol. Soc. ' for the present year, p. 254. The 

 strata immediately overlying are marine, and contain fossils that are either 

 Palseocene or very high Cretaceous, but the age of the boulder-bed itself is some- 

 what doubtful. The occurrence of large boulders in a fine silt appears to indicate 

 glacial conditions, as in the Talchir beds of India, of which there is a possibility 

 that this Salt Range bed may be a representative, although most of those who 

 have examined the ground think it to belong to a much later geological period, and 

 associate it with the overlying Upper Cretaceous or Palseoceue strata. 



12. On a Striated and Facetted Fragment from Cliel Hill Olive Conglo- 

 merate, Salt Range, Punjab.^ Bij A. B. Wynne, F.G.S. 



Picked up bv Dr. H. K. Warth, June 10, 1886. 



Latitude, .32° 45' N. ; longitude, 73° 15' E. (about). 



Size, Z\ inches x 2\ inches x 2 inches. 



Weight, 10:^ ounces. 



Material, reddish-brown porphyritic felsite, pale. 



Age of containing beds probably late Pre-Tertiary (but said by some to be 

 Palceozoic), smoothed, polished, and striated on twelve different surfaces, giving it 

 at first sight the appearance of an imperfect crystal. Of these surfaces about six 

 are perfectly flat, others somewhat curved. 



On the largest surface the striation is fine, nearly in the direction of the longest 

 axis ; on other surfaces the strife cross this direction at various acute angles, ranging 

 from 23° to 80° or 85° from the more axial direction. On some of the faces, 

 making most obtuse angles with each other, the direction of the striae varies 

 least. 



The specimen is slightly marked superficially by the tin-box in which it 

 travelled; its planes show small cavities, once apparently occupied by pyrites 

 crystals, which being dislodged have initiated and caused striation as though they 

 had been used as engraving tools. 



From the positions of a large number of the facets (6), all upon one side of the 

 specimen, all contiguous and of unequal size, together with the slight variation in 

 direction of their striation, it would appear that this pebble, with whatever it was 

 embedded in, made about a half-revolution almost around its major axis by six 

 separate stages, and underwent severe grinding and polishing at each stage, to a 

 degree almost artificially perfect. 



The state of things which would permit of this action, supposing the pebble to 

 have been grasped and held by a resisting matrix of ice, whatever its bulk, effec- 



> Published in full in Geol. Mag. Dec. 3, vol. iii. p. 492, Nov. 1886. 



