Royal Society. 527 



Memoirs of the Geological Survey. Explanation of Ma}) 48 E.S.E 



and adjoining part of 48 N.E. The Geology of the Eastern End 



of Essex ( Walton-Naze and Harwich). By W. Whitaker, B.A. 



Lond., F.G.S. London, 1877. (8vo, pp. 32.) 



This short memoir completes the geological descriptions, by the 



Geological Survey, of the area directly bordering the estuary of the 



Thames, and is supplementary to the author's longer memoir on 



the Geology of the London Basin, 1872. It is also the first 



memoir issued by the Geological Survey which notices the Crag 



Formation, so rich in fossils, and valuable as a source of the phos- 



phatic nodules and fossils, called " coprolites," used in making 



artificial manures. 



The London Clay and its cement-stones come to be first de- 

 scribed ; then the Red Crag of Beaumont, Walton-Naze, and near 

 Wrabness and Harwich, is carefully noticed, in brief, both from 

 the author's recent observation on its dwindling remnants, and 

 from the results of the long-continued researches of the Messrs. 

 Wood, Prof. Prestwich, and others. The old gravels, sands, and 

 brick-earths, and the later alluvium, blown sand, and shingle, also 

 receive attention. In noting the physical features of this clay 

 district, with its local cappings of gravel, and its alluvial flats, the 

 great waste of the seaclifrs is of course mentioned. We may sug- 

 gest that if the Government were to apply a small sum of money 

 to allow of the Coast Guard making accurate periodical measure- 

 ments, from the sea to inland marks, on those parts of the British 

 coasts subject to great degradation, some definite bases for calcu- 

 lating the continuous loss of land, and occasional gain from the 

 sea, would be obtained before many years have elapsed. 



Several valuable well-sections are recorded by Mr. Whitaker in 

 Appendix I. ; and Mr. Etheridge gives some carefully revised lists 

 of fossils in Appendix II. 



LXXII. Proceedings of Learned Societies. 



KOYAL SOCIETY. 

 [Continued from p. 477.] 



Dec. 14, 1876. — Dr. J. Dalton Hooker, C.B., President, in the 



Chair. 

 r PHE following paper was read : — 



-*- " Note on the Photographic Spectra of Stars." By William 

 Huggins, D.C.L., LL.D., E.B.S. 



In the year 1868 Dr. Miller and myself obtained the photograph 

 of the spectrum of Sirius. 



" On the 27th January, 1863, and on the 3rd March of the same 

 year, when the spectrum of this star (Sirius) was caused to fall 

 upon a sensitive collodion surface, an intense spectrum of the more 

 refrangible part was obtained. Erom want of accurate adjustment 

 of the focus, or from the motion of the star not being exactly 



