Correspondence — Mr. T. Mellard Reade. 143 



perhaps the equivalent of younger members of the Cretaceous series, 

 not elsewhere found in our islands, or, it may be, they must be 

 regarded as belonging to periods intermediate between the Cretaceous 

 and Tertiary epochs. It is greatly to be regretted that these Cre- 

 taceous deposits of the Western Highlands are so unfavourably 

 displayed for our study as to present scarcely any facilities for the 

 collection of their fossils ; for these, if found, might be expected to 

 throw a flood of light on some of the most obscure palgeontological 

 problems of the present day. 



Although the comparison and correlation of the Secondary strata 

 of the Highlands with those of other areas, and the discussion of the 

 questions of ancient Physical Geography thereby suggested, are 

 reserved for the fourth and concluding part of his memoir, the author 

 takes the opportunity of making reference, in bringing the present 

 section of his work to a close, to several problems on which the 

 phenomena now described appear to throw important light. In 

 opposition to a recent speculation which would bring into actual 

 continuity the present bed of the Atlantic and the old Chalk strata 

 of our island, he points to the estuarine strata of the Hebrides as 

 demonstrating the presence of land in that area during the Cretaceous 

 epoch. He also remarks on the singular agreement of the conditions 

 of deposition of both the Silurian and Cretaceous strata of the 

 Scottish Highlands and those of the North American Continent. 

 But he more especially insists on the proofs, which we now have, 

 that the Highlands of Scotland, as well as the greater part of the 

 remainder of the British Islands, were once covered by great deposits 

 of Secondary strata, and that the area has been subjected to enor- 

 mous and oft-repeated denudation. He dwells on the evidence of 

 the vast quantities of material which have been removed subse- 

 quently to the Mesozoic and even to the Miocene pei'iod, and he 

 maintains the conclusion that many, if not all, of the great surface- 

 features of the Highlands must have been produced during the very 

 latest division of the Tertiary epoch, namely the Pliocene. 



coK/E-iEsipoisrzDszsrcE. 



INDUCED STETTCTUEE IN STONE. 



Sir, — A very remarkable exfoliated piece of sandstone from an 

 urn forming part of a tombstone was brought me by a mason a 

 short time ago. It is from the base or pillar of the urn itself, and 

 measures 9 in. by 6 in., varying in thickness from -^ to -^ of an 

 inch. The outside surface had been worked and rubbed in forming 

 the urn, and one side of the exfoliated piece consists of this worked 

 surface perfectly preserved. The pedestal has a horizontal and 

 vertical curvature, and when laid on the table the exfoliated piece 

 rises fully two inches in the quickest part of the curve. I exhibited 

 this specimen at the last meeting of the Liverpool Geological 

 Society, when some scepticism was evinced as to its being genuine 



