64 



rill'; UK A(iK l\ C.WAItA. 



tlu'si' ;ii(' iiiiisscs of tlic liiiid siilidstoiK's ol' I Ik? lower 

 Siluriilll lock of the sol.lli coii.sl, ;|||<1 occiisioliallv, tlioll^fli 



rarely, blocks of ihc u\t\)vv Siluriiiii liiMcsloiic of the 

 iiiliiiid hills to the south. 



The iioiildci's of ihis licit, tlioiitih suitioimry in smiiiiici', 

 iiiv often moved hy the coast-ice ji winter. This is well 

 seen where they have heeii reiMo\»Ml to foini tiiieks 

 for launching boats. In this case it is not, unusual 

 to find in the spiiui^ that such tracks have been partially 

 relilled with boulders. On my own projierty, a tiaek of 

 thi.s kind was completely bIocke(l a few years a^o by an 

 ani^idar boulder of sandstone nine feet in length, which 

 had been lifted from a spot a few feet distant; and it i.s 

 ([uite usual to find in a Iniat-track, cleared in the pi'e\i(ais 

 summer, a d(t/eu Inaddcrs of two feet or more in dianu'ter 

 that ha\'e been droi)ped in it l»y tlu^ winter ice. Whether 

 any of these blocks are bein^- drifted at the ]tresent time 

 from the north shore is not known : but they are mo\-ei| 

 freely up and down the coast, and in dl•e<l^•in^ in de|»tlis 

 of ei,Li;ht to (ift.eeii fathoms, I ha\-e found e\ideiiee that 

 large boulders are not unconnnon tai the bottom ; and 

 ,jndgin,n- fidui the small specimens taken u|t by the dii'di^c, 

 they are sinnlar to those on the shore, though ai»i>ar(!ntly 

 with a larger projxation of Hat, slaty fragments. 



If the coast were now in jirocess of subsidence, there 

 can b(! no question that the; l)oulders would l)e pushe»l 

 uj)ward, and woidd eventually foi'ui sheets and ridges of 

 boulders embedded in mud, much in the manner of the 

 marine boulder-clays now found inland. 



Above high water, on certain portions of the coast, 

 there is a low terrace, only a lew feet above the sea, and 

 consisting of sand, shingle, and gra\'el, often with frag- 

 ments of marine shells. IJoulders are not numerous on 



