230 Dr. ManteWs Isle of Wight. 



5. The mechanical theory of terrestrial magnetism which has 

 been under discussion, must be true in all its essential features. 



6. We may derive the magnetic elements by very simple for- 

 mula, and with an accuracy equal to that of Gauss's formulae, 

 from a very small number of magnetic data determined by ob- 

 servation, and the mean annual temperature of the place. 



The great importance of these results cannot well be question- 

 ed. Whether or not they be regarded as supporting the theoret- 

 ical views of the physical nature of magnetism which have been 

 briefly alluded to, they cannot fail, it would seem, to throw some 

 additional light upon this hitherto mysterious subject. They al- 

 so link together in the closest bonds of union, the two sciences 

 of Terrestrial Magnetism and Meteorology, and confer a new 

 value upon the observations made in each of these two great de- 

 partments of science. 



Art. XIX.— Notice of Dr. MantelVs Isle of Wight* 



While mentioning this new work of Dr. Mantell, we can re- 

 spond to the sentiment of Scott f In earlier years we visited the 

 • beautiful island," and found in it the most remarkable features 

 —topographical, geological, picturesque and agricultural : while 

 in connexion with the vicinal coast of Dorset, Hampshire and 

 bussex it is full of interesting historical associations. Upon this 

 coast the Romans first made their landing— the Saxons, Danes, 

 and Normans followed, and it is easy to understand that the geo- 

 logical events recorded in the strata, and the historical events 

 that have clustered on the surface, may combine to impart to thi 

 region peculiar attractions. It lies on the narrow channel which 

 divides England from France, and in a climate which is regarded 

 as the mildest m Great Britain. 



This region is rich in the fossil treasures of the tertiary, the 

 chalk, and the Wealden; and Dr. Mantell has done much to ex- 

 plore and make known the geology of the S.E. of England. 

 1 he science is greatly indebted to him for his very able works 

 on local geology, as well as for his comprehensive Survey of the 

 Wonders of Geology, and of the Medals of the Creation. 



pages 



Wi 



^ — 



"Geological Excursions round the Isle of Wight and along the adjacent coasts 

 ot DoweUhire, illustrative of the most interesting geological phenomena and or- 

 ganic remains. By Gideon Ai^rxob Ma*t«£V." Esq" LL D-, F.R.S., Author 

 «t The Medals of the Creation," « Thoughts on Animalcules," &c. 



wm: aaasass ^t&^^rpszv&r through whaterer patt of the 



