1883.] 185 [Dale 



a, c, consist of the peculiar conglomerate above described; the central one 

 consists of a hard Graywacke slate, and a very singular and puzzling rock, 

 which I shall venture to describe as a metamorphic slate. — The layers of 

 the Graywacke slate and amphibolic aggregate run north and south and 

 dip west 60° to 70°. And this, as already mentioned, is the direction in 

 which the nodules and schistose layers of the cement of the conglomerate 

 are placed. But no strata planes are to be seen corresponding to the dip 

 and direction of the slate." 1 



This is accompanied by a rough diagram answering the purpose 

 of both a topographical and geological map, in which three con- 

 verging ridges are figured. On his general geological map the 

 whole tract appears as " Gray Wacke," but, on page 548, in 

 describing the lithological character of this " amphibolic aggre- 

 gate," he remarks : " Had I found it among primary rocks, I 

 should have regarded it as by no means an anomaly there ; espe- 

 cially after finding in it a vein, four inches wide, of crystallized 

 zoisite." 



Prof. Ch. Hitchcock merely alludes to this locality : 



" The range is more than a mile wide, showing itself most southerly below 

 Purgatory, composing the Hanging Rocks and Paradise, and probably 

 underlying the drift as far north as Sandy Point in Portsmouth. — There 

 are three ridges of this conglomerate at its southern part, — Purgatory 

 being located in the western, and the Hanging Rocks composing the eastern 

 one. The middle ridge is a hard, gritty rock." 2 



In his map the whole of Paradise is set down as conglomerate 

 and grit. 



Prof. N. S. Shaler remarks : 



" The mass of conglomerate and associated materials known as Paradise 

 Rocks also shows some interesting phenomena. These rocks consist of a 

 set of ridges of steeply inclined beds of various hardness, which owe their 

 position to a number of parallel faults extending in a north and south 

 direction with a considerable throw, so that the projecting edges of the 

 rocks rise at sharp angles to the height of from 50 to 150 feet above the sea 

 level. Carefully tracing these rocks in the direction in which they are 

 continued to the northward, it becomes evident that, at the time when they 

 were formed, the ridges continued for several hundred feet to the north- 

 ward of the base of the slopes which lead down to the comparatively low 

 land which now bounds them on that side. We cannot resist the conviction 

 that the powerful agent which has cut away these solid masses of rock was 



1 Geol. of Mass., p. 535, 536. 2 Qeol. of the Island of Aquidneck, p. 113. 



