PROCEEDINGS OF GEOLOGICAL SOCIETIES. 



71 



land and Freshwater shells, all of recent species, together with 

 remains of fishes and insects ; and for the list of which I refer to 

 Sir Charles Lyell's paper. Some mammalian remains have also been 

 found, bat the only bone I myself obtained was, apparently, that of 

 the ox. Now this deposit is nnderlaid throughout its width, and 

 thereby distinctly separated from the Boulder clay, by the bed of 

 ochreous flint gravel (& 4 ), two to four feet thick. It is overlaid by 

 by another bed of gravel and brick earth (a), of five to ten feet, also 

 newer than the sands and gravel (/) . The way in which these two 

 gravels merge one into the other, at each end of the section, is very 

 instructive. 



In superposition, therefore, above the Boulder clay, this bed resem- 

 bles the Hoxne deposit, as it does likewise in its Freshwater character 

 and shells, and in its unconformity to the existing line of drainage ; 

 for a reference to the section will show that this Mundesley deposit 

 is not exactly coincident with the line of the present valley. I con- 

 sider it is a deposit in which flint implements like those of Hoxne 

 may probably be found — especially, however, would I suggest a 

 careful search to be made in sandy part (& 1 ), and the gravel (6 4 ). 

 The determination of the exact superposition of this bed is further of 

 consequence, inasmuch as some important questions, connected with 

 the fauna of the pre-glacial and post-glacial periods, hinges materially 

 upon it. In this inquiry, therefore, I have, for the present, limited 

 myself merely to the question of position, and to pointing out the 

 presence of the Freshwater shells at h 3 , and the band of mussels in A 2 , 

 otherwise leaving aside the other important question of organic 

 remains.* 



I have annexed a rough but proportionate and measured section of 

 the beds, taken at different favourable periods. 



PROCEEDINGS OF GEOLOGICAL SOCIETIES. 



Royal Institution. —Dr. Tyndall's lecture on the 18th ult. was a memorable 

 Diie iu the annals of even that famous institution, of which Faraday is one of 

 the brightest ornamants. The Radiation of Heat is an old and familiar 

 subject; but Professor Tyndall has crowned it with some new and most important 

 Pacts — " On the Influence of Gases and Vapours upon the Rays of Heat 

 Emanating from a Dark Hot Surface." 



Before an audience of five hundred persons, of the highest rank and education 

 lb the metropolis, Dr. Tyndall, pale with anxiety for the success of those experi- 

 ments, almost unrivalled in their delicacy, on which the enunciation of his 

 .mportant facts depended, demonstrated forcibly the new truths that the heat 

 radiated from dark bodies differs in many respects from the heat radiated by 



* I am happy to say that the fossils, both of the Forest bed and of the Fresh- 

 water beds (bj, are now engaging the active attention of a very zealous observer, 

 who will, no doubt, add materially to our present lists. 



