802 
Proceedings of the Royal Society 
Linton. — (1) On Dry! aw Farm, a limestone boulder x 3J x 3 
feet, met with in cutting a deep trench through boulder clay. The 
longer axis N.N.W. The FT.W. end more pointed than east end, 
also well rounded and polished by friction. Boulder tolerably flat on 
upper side, but no striae visible. On each of the two sides, meeting 
at N. W. end, boulder not only smoothed but striated — chiefly along 
side facing N.N'.W. 
The nearest rocks of same composition as boulder, are in Garlton 
Hill, about 6 miles distant, and bearing W. by H. (by compass). 
If agent which smoothed and striated the sides of the boulder 
came, as is probable, from the westward, it seems, when it reached 
the boulder at A C (its west end), to have divided into two streams, — 
Drylaw Boulder. 
one, A B, flowing along north side E.N.E., the^other, C D, along the 
south side S.S.E. 
The clay in which the boulder was buried, contained blocks and 
pebbles, some of them, soft (such as shale, coal, &c., from the west), 
and others, hard (rock or greenstone, granite, &c.), quite capable of 
smoothing and striating the boulder, if driven and squeezed against 
it by some agent of sufhcient weight and magnitude. 
(2) In the village of Linton, several portions of porphyritic 
rock recently exposed, which are smoothed and striated. On 
one portion of rock, the surface of which is horizontal, the direction 
of striae is W.H.W. and E.S.E. 
