lieviews and Notices respecting New Booh. 127 



distance rendered by Geology to Physics. This same Dolcoath mine, 

 whose phaenomena of veins were so singuhir, was the one selected by 

 Prof. Airy for determining the density of the earth. Mr. Sedgwick 

 remarked, that fissures caused by crystallization were, in general, 

 very small ; and that joints seldom coincided with rents ; — that in 

 districts where granite approaches slate rocks, we may be certain of 

 finding the richest metalliferous deposits. Practical miners had often 

 whimsical ideas of the origin of metals. One of them had once 

 gravely informed him that they were caused by peat^ and had shown 

 wiiat he conceived to be a convincing proof, namely, their existence 

 under a peat bog in his neighbourhood, and occurrence nowhere else 

 in the same vicinity. — Sir W. R. Hamilton testified also to the impor- 

 tance of new applications of mathematico-physical science. Not only 

 would new views open, but even new methods of analysis would 

 arise to assist the investigator. 



Dr. W. H. Crook made some observations on the unity of the Coal 

 Deposits of England. The object of this communication was to show 

 that the coal-fields of England and Wales were not distinct basins, 

 but that the supposed basins were only portions which had been de- 

 tached and elevated by the agency of syenitic and trap rocks, of a 

 much larger deposit, spread over the greater part of the districts now 

 covered by the new red sandstone. Of the vegetable origin of coal 

 there is now no doubt : the only question unsettled is, did the plants 

 supplying it grow on the spots where it is found, or were they trans- 

 ported ? Dr. Crook inclined to the latter opinion, and conceives that 

 this view may be extended to the coal of Belgium, of the north of 

 France, and the north-west of Germany 3 the carboniferous beds of 

 those countries having originated, in his opinion, in a drift of vege- 

 table substances from countries lying to the east or E.S.E. of them ; 

 and he also thought, that the extent and richness of the English coal- 

 fields, especially in the Midland counties, arose in a considerable degree 

 from the impediments ofl'ered to the transit of the drifted matter by 

 the slate and other ancient formations of Wales and Cumberland. He 

 considered, that the Charnwood Forest rocks had elevated the coal- 

 field near it, and a similar elevation had taken place at Nuneaton. 



Mr. Greenough considered the idea of Dr. Crook as very probable; 

 but observed, that the deepest of our coal basins had been found to be 

 in South Wales. — Mr. Young, from Nova Scotia, stated, that large 

 deposits of coals had been found in that country. — AtheneBum, No.b\7. 



XX. Reviews and Notices respecti?ig New Books, 

 Electricity ; its Nature^ Operation, and Importance in the PhcEnomena 

 of the Universe. By W. Leithead, Secretary to the London EleC' 

 trical Society. London, 1837, V2mo. 



WE had occasion to notice lately an observation by a distinguished 

 foreign contemporary, in which the writings of some of our coun- 

 trymen in the department of electricity were treated as having contri- 

 buted but little to its advancement. We have since, however, in 

 addition to a Journal of Electricity, had the establishment of an 



