74 Intelligence and Miscellaneous Articles. 



diameter retain their angularity for a very long period indeed, 

 remaining, under ordinary circumstances, unrounded; but they are 

 much more rapidly rounded by the action of wind. It is thus 

 probable that rounded grains of this kind in some of the older 

 rocks, as, for example, certain of the Triassic sandstones, may be 

 the result of a^olian action. 



The Chair was then taken by J. W. Hulke, Esq., F.R.S.,Y.P.G.S. 



2. " On a New Species of Trigonia from the Purbeck Beds of the 

 Yale of Wardour." By E. Etheridge, Esq., F.R.S., President. With 

 a Note on the Stratigraphical Position of the Fossil by the Rev. W. 

 R. Andrews. 



XI. Intelligence and Miscellaneous Articles. 

 note on mr. browne's paper st on action at a distance." by 



REV. A. J. C. ALLEN, B.A., FELLOW AND ASSISTANT TUTOR OF 

 PETERHOUSE, CAMBRIDGE. 



IN his paper in the Phil. Mag. for December 1880, Mr. Browne 

 certainly appears to establish the proposition that we cannot 

 explain the phenomena of cohesion &c. in a satisfactory way by 

 means of the direct impact of bodies ; and then he goes on to 

 deduce from this that action at a distance (a very small distance 

 indeed, but still finite) must exist in these cases, and therefore may 

 be equally well allowed in the case of bodies at a great distance, as 

 the earth and sun. Now it appears to me that in reality very 

 much is gained in the scientific explanation of phenomena when 

 they are transferred from the region of action at great distances 

 to action at distances such as intervene between the particles of 

 solid bodies. I cannot explain this better than by quoting the 

 words of Clerk Maxwell, who has himself done so much in the 

 direction of getting rid of action at a distance by his explanation 

 of electrical and magnetic phenomena by means of stress in the 

 medium which fills the electrical or magnetic field. 



" When we see one body acting on another at a distance, before 

 we assume that the one acts directly on the other we generally 

 inquire whether there is any material connexion between the two 

 bodies ; and if we find strings or rods, or framework of any kind 

 capable of accounting for the observed action between the bodies, 

 we prefer to explain the action by means of the intermediate con- 

 nexions, rather than admit the notion of direct action at a distance. 



" Thus, when two particles are connected by a straight or curved 

 rod, the action between the particles is always along the line join- 

 ing them ; but we account for this action by means of a system of 

 internal forces in the substance of the rod. The existence of these 

 internal forces is deduced entirely from observation of the effect of 

 external forces on the rod; and the internal forces themselves are 



