scientific Reviews. ^% 



the surrounding strata preventing the expansion which takes place 

 in the artificial caking of coal. Leaders of charred coal were ob- 

 served, also extending upwards from the mixture below. Mr. F. 

 Forster has described the nature and properties of some of these 

 specimens. The basalt, from the mixed stratum of basalt and coke, 

 IS fine-grained and compact, and interspersed with crystals of feld- 

 spar : sp. gr. 2.672 : fuses into a brown glass. The coke was mix- 

 ea with irregular streaks of carbonate of lime, and rather abundant- 

 ly interspersed with sulphuret of iron : sp. gr. 1.957, that of the 

 coal which it represents being 1.275 : on calcination, it gave about 

 23 per cent, of lime and iron. But in other cases^ specimens were 

 found in actual contact with basalt, which gave 64 parts of carbon, 

 and 34 of volatile matter in the 100. 



The bed of whin described by W. C. Trevelyan, Esq. and mis- 

 taken bv Westgarth Forster, (who is no geologist,) for the great 

 whin-sill, occurs in the lead measures at Stanhope in Weardale, 

 and is only of partial extent. It appears to occur in the fourth or 

 tliree-yard limestone. 



The basalt of Ratcheugh Crag, the subject of Mr. Francis For- 

 ster's memoir, appears to be a continuation of the same bed which 

 forms the Dunstanborough Castle CliiF, as well as the bold escarp- 

 ment extending southward behind Craster Sea Houses. It forms 

 a cliff of about nine feet high, and faces to the west. The effect of 

 the basalt on the limestone, and their relation to the dyke of 

 Snableases Quarry, are extremely interesting. 



We observe, as a general result, that the geologists of Newcastle 

 are unanimous in their opinion on the origin and nature of basalt 

 and diorites. Their labours have already tended to throw much light 

 upon the phenomena and accidents attending their distribution in 

 tlie coal and lead measures. The excellent tables which they pos- 

 sess of these strata, would enable the merest tyro to study them 

 \vith advantage ; and we hope that, with a little more method and 

 the same perseverance, we shall gradually have the whole of these 

 phenomena laid before us in an analytical view, or so as to be ap- 

 plied to geognostic generalizations. 



Before we leave the geological part of the transactions, we must 

 allude, in terms of high commendation, to two other memoirs, one 

 by Mr. William Hutton on the new red sandstone of the county of 

 Durham, below the magnesian limestone ; the other, entitled Obser- 

 vations on the South Welsh Coal-Basin, by Mr, Francis Forster. 

 The labours of Professor Sedgewick have gained us a more inti- 

 mate acquaintance with the situation of the magnesian limestone of 

 Sunderland and Hartlepool. The new red sandstone which occurs 

 beneath it, is an equivalent to the red sandstone, named, on ac- 

 count of its being more metalliferous, red dead Her by the Ger- 

 man miners ; or to the Exeter red conglomerate : it is the lowest 

 of three beds of new red sandstone, as given in Mr. de la Beche's 

 table of sedimentary deposits. The distribution and the demarca- 



