XVIII. — A SJcetch of the Structure of the Eastern Alps ; with Sections 

 through the Newer Formations on tlie Northern Flanks of the Chain^ 

 and through the Tertiary Deposits of Styria, &;c. &;c. 



By the Rev. ADAM SEDGWICK, Pres. Geol. Soc. F.R.S. &c. 



(WOODWARDIAN PROFESSOR IN THE UNIVERSITY OF CAMBRIDGE.) 



And RODERICK IMPEY MURCHISON,Esq. Sec.G.S. P.R.S.F.L.S.&c. 



[R,ead Nov. 6, 20; Dec, 4, 1829 : and March 5, 1830.] 



With Supplementary Observations, Sectiofis, and a Map. 

 By Roderick Impey Murchison, Esq. Sec. G.S. F.R.S. F.L.S. &c. 



[Read Jan. 19, and Feb. 2, 1831.] 



Preface. 

 IHE following Memoir contains a series of papers, presented by the authors 

 after their visit to the Austrian and Bavarian Alps in 1829, which would have 

 been already published, but for an unavoidable delay in printing the present 

 Part of the Transactions. The abstracts of these papers no sooner appeared 

 than they were combated, both in British and foreign journals, by Dr. Boue, 

 who, in his system, placed in the lower green-sand what the authors regarded 

 as a connecting link between the great secondary and tertiary deposits. As, 

 however, in confirmation of his own views, he cited phenomena they had not 

 seen, it was important that at least one of them should visit the places referred 

 to ; and it also became necessary to describe in greater detail the formations 

 they had considered of the age of the green-sand and chalk, and to prove them 

 inferior to those peculiar deposits which they regarded as intermediate between 

 the chalk and the well-known tertiary groups. 



For this purpose Mr. Murchison, during the summer of 1830, again visited 

 the Eastern Alps, and communicated the result of his observations in a memoir, 

 of which an abstract has been recently published in the Proceedings of the 

 Society. 



During the progress of the present Part of the Transactions, it became a 

 question with the Council in what order the papers on the Alps should be 



