Mineralogy and Geology of apart of Nova Scotia. 321 



surface, and on examination at low water, it appears to con- 

 sist of distinct columnar greenstone, whose individual faces 

 are probably the summits of long columns rising vertically 

 from deep foundations. These faces, which are of course 

 subject to the periodical overflow of the tide, present, 

 from the action of the sea, assisted by the motion of sand 

 and pebbles, shallow, basin like cavities, regularly curving 

 from the centre up to the polished brim, formed by a sub- 

 stance of a different nature from the bottom. This sub- 

 stance, which never exceeds half an inch in thickness, is a 

 quartzose cement. It entirely surrounds the columns ; pre- 

 venting their immediate contact ; and from its less obvious 

 marks of dimunition, it forms small projections rising above 

 their surfaces, serving to protect most effectually, that portion 

 nearest approaching the sides. Thus the comparatively 

 greater diminution of matter towards that point is readily 

 accounted for, and the formation of these basin like cavities 

 would seem the natural effect of long continued exposure, 

 did they not themselves prove satisfactorily what causes have 

 operated in forming them. We also observed several col- 

 umns beyond the reach of the sea, which exhibited these ap- 

 pearances in a less striking manner, though to an extent suf- 

 ficient to prove that the effects of ordinary causes have a di- 

 rect tendency to produce eventually these depressions. This 

 greenstone, as regards internal characters, corresponds, al- 

 most precisely, with that from Little River before mentioned. 



About a mile west of this cove, among water worn masses 

 which form a loose pavement descending into the sea, we 

 observed several egg shaped masses of amygdaloid, exhibit- 

 ing on their surfaces, small globular concretions of helio- 

 trope, invested with green earth, and presenting all the inter- 

 mediate shades of color, from transparent chalcedony to an 

 almost opaque green. We also picked up several imperfect- 

 ly polished masses of greenstone porphyry of a fine texture* 

 exhibiting distinct faces of crystals of white feldspar in the 

 form of a parallelogram : but we did not succeed in finding 

 this rock in place. 



Leaving Chute's Cove, and proceeding about six miles 

 eastwardly, we arrive at St. Croix Cove. At this place, the 

 rocks resume their abruptness, and present lofty precipices of 

 columnar trap, resting on amygdaloid, which abounds with 

 its usual zeolites. The shape of the cavities which the 

 amygdaloid presents, is quite singular, Instead of the splie- 



Vol. XIV.— No. 2. 3 5 



