Mr. N. Wood on the Geology of Northumberland, 8(c. 307 



harbour for a short distance also, when we meet with coarse gritty 

 Sandstone rocks rising north. 



From the commencement of the Section to and beyond the Coquet, 

 those rocks which have withstood the action of the sea, viz. : the coarse 

 Sandstones and Shale, are clearly referable to the Coal Measures. How 

 far beyond the mouth of the Coquet the Coal Measures extend, could 

 not be ascertained, but the rocks midway between that river and Ale- 

 mouth shew, that they do extend beyond that place. After passing 

 the flat sandy beach, north of Alemouth, the rocks, however, assume a 

 quite different character, the Sandstones become more decidedly gritty, 

 consisting of large grains of rounded, and frequently pieces of angular. 

 Quartz, agglutinated by a ferruginous cement, and presenting every 

 characteristic of the " Millstone Grit." 



The first group of these rocks, called the Alemouth rocks, are low, 

 rising north, 1 in 8 or 9, accompanied with thick beds of hard black 

 Shale. An interval of sandy beach then occurs, beyond which a reef 

 of rocks stretches into the sea, called the Seaton or Bally-car Rocks, these 

 consist of a thick bed of very coarse gritty Sandstone, with large angu- 

 lar fragments of Quartz imbedded. From this, northward to Boulmer, 

 beds of Grit and Shale alternate, rising north ; when the first observable 

 bed of Limestone occurs, from 4 to 5 yards thick, abounding in En- 

 crinites and Bivalve Shells, corresponding in every respect with the 

 blue Encrinal Limestone of the Lead Measures. Line of direction, 

 N. 70 E., rise north 10°. 



Underneath the Limestone lies a hard marly Sandstone, then thin 

 beds of Plate, containing muscle shells in abundance, below which are 

 beds of Plate and Sandstone alternating, rising north, with a bed of 

 Coal, apparently from 20 to 30 feet below the Limestone. Similar 

 alternations of Shale and Sandstone take place to Boulmer Point, when 

 a small bay occurs, the north side of which exhibits the beds of Sand- 

 stone much contorted and disturbed by Slip Dykes. 



A little beyond this, and nearly opposite Howick, a Slip Dyke of 

 considerable magnitude occurs, throwing in a bed of black Limestone, 

 several yards thick, resting on Plate, and dipping north 20°. Upon 



VOL. I. T t 



