106 THE TRIAS OR NEW RED SANDSTONE. 



summit of the rock. By scrambling at low tide around the south side, 

 we find that this, like the basalt of Blomidon, is a thick irregular bed, 

 and that amygdaloid and tufa succeed it in descending order. On the 

 western side these last rocks occupy nearly the whole of the cliff, and 

 may, when examined from a distance, be seen to consist of several 

 beds distinguishable by different shades of colour. In some lights 

 this difference is very perceptible. On this side the basaltic trap still 

 appears, but it forms only a thin bed, capping the amygdaloid and 

 tufa. Under all these beds, and in the north-west corner of the island, 

 the sandstone peeps forth, dipping to the south-east. 



The trap of Partridge Island contains a variety of interesting crys- 

 tallized minerals. A honey-yellow variety of stilbite, crystallized in 

 fine sheaf-like aggregations of crystals, is especially abundant, forming 

 veins running up the face of the cliff. Being one of the most acces- 

 sible and easily explored portions of the formation, this place has been 

 much ransacked by mineralogists and amateurs ; still large quantities 

 of fine specimens may generally be seen going to waste on its beach. 

 Amethyst, agate, chabazite, heulandite, apophyllite, and calc spar, may 

 also be studied in some of their most beautiful forms at Partridge 

 Island. The whole of these minerals have been introduced by the 

 action of water, trickling through the numerous fissures of the porous 

 amygdaloid and tufa, rocks which perhaps, more than any others, are 

 fitted to yield to water thus permeating them the materials of crys- 

 tallized silicious compounds. 



Westward of Partridge Island, vertical and contorted Carboniferous 

 rocks occupy the shore as far as Cape Sharp, three miles distant. 

 This promontory, which, like Partridge Island, presents a precipitous 

 front to the bay, and slopes toward the land side, consists of trap 

 resting on red sandstone. Here, however, trap conglomerate takes the 

 place of the finer tnfaceous matter seen at Partridge Island. It will 

 be observed that though the red sandstone is not at these places seen 

 very distinctly to rest on the Carboniferous rocks, the former underlies 

 the trap at a gentle angle, and dips southwards, or from the latter, 

 while these are contorted and disturbed in the most extreme manner, 

 serving at least to confirm the evidence, noticed at other places, of the 

 later date of the New Red. These contorted Carboniferous sandstones 

 and shales must have formed a coast line, at the time when the red 

 sand was washing in the sea, and the trap and scoriae being belched 

 forth from submarine vents. 



Beyond Cape Sharp, with the exception of the isolated mass of 

 Spencer's Island, which I have not visited, we see nothing of the trap 

 or red sandstone till we reach Cape d'Or, the last and noblest mass on 



