1879.] Mr Fisher, On implement-hearing loams in Suffolk. 285 



Then in order that the force between two such spheres may be the 

 same as that between two hydrogen atoms, we must have 



^, = 7300. 

 T 



If we suppose the amplitude -^^ of the radius, the number- of 

 pulsations in a second will be about 



3 . 65 X 10^ 



The number of vibrations of the ether for the extreme red in 

 the spectrum is about 4 . 7 x 10". 



It is to be noticed that if we suppose the ratio of the ampli- 

 tude to the size of the sphere constant, then, in order that the 

 attraction between two spheres must be proportional to the masses, 

 the time of pulsation must be the same for all — the same condi- 

 tion we have already found that they should attract at all. 



November 10, 1879. 



Professor Newton, President, in the Chair. 



The President referred to the great loss sustained by the Society 

 and the University by the death of Professor Clerk Maxwell, which 

 occurred on November 5. 



The following communications were made to the Society : — 



(1) Mr O. Fisher, M.A. On implement-hearing loams in 

 Suffolk. 



I have to relate to you this evening what I have seen under 

 the guidance of Mr Skertchly in the district which he has rendered 

 famous by his investigations of the loams containing worked flints. 

 I visited a portion of this district in November, 1876, in company 

 with Mr Belt, the naturalist, traveller, and geologist, who has since 

 been lost to science by his early death. Mr Skertchly then con- 

 ducted us over a portion of ground around Brandon, and showed 

 us in particular three sections. It will be well to premise that 

 this country consists principally of chalk with an . undulating 

 surface, nowhere attaining any considerable elevation. The chalk 

 contains beds of flint of a character especially suited for the 

 manufacture of all kinds of implements — a manufacture still 

 carried on. The surface is covered with an incoherent brownish 

 sand, probably spread over it by the action of wind. In some 

 places are depressions in the surface of the chalk, which are 

 occupied by later deposits, which have probably at one time 

 extended beyond the depressions in which they are now seen, 

 but have been elsewhere denuded off. 



