1B26. Proceedings of Philosophical Societies. 61 



Article XII. 



Proceedings of Philosophical Societies. 



ROYAL SOCIETY. 



May 2b. — The Right Hon. Sturges Bourne, and Dr. A.V, 

 Wilson Phihp, were admitted Fellows of the Society ; and the 

 reading of Mr. Osier's paper. On the Burrowing and Boring 

 Marine Animals, was concluded. 



In this paper, the operations and mechanism of burrowing 

 and boring, as practised by various marine animals, belonging 

 to the classes Mo//w5ca and il??we/«c?e5, are first minutely described. 

 Facts are then adduced, tending strongly to prove, that the 

 Lithophagi effect their perforations, not by mechanical means, 

 but by a solvent fluid, which, however, being secreted only 

 when required for use by the animal, the author has not been 

 able to detect by chemical tests. These animals perforate cal- 

 careous stone, and shell, but their progress is stopped by siUce- 

 ous or argillaceous matter, on which they are unable to act ; thuj* 

 a thin layer of clay occurring in a rock which they are perforat- 

 ing, forms to them an impassable obstacle. Another important 

 fact related in this paper, having the same bearing, is as follows : 

 — The Saocicavce often exert their boring powers on the shells of 

 contiguous individuals of their own species ; and so long as they 

 have not penetrated through them, no notice is taken of it by 

 the animals attacked ; but when the perforation is complete, or 

 very nearly so, the aperture is immediately filled up, not with 

 shell, but with a yellow animal-substance, insoluble even in the 

 mineral acids. 



Junel. — The following papers were read : — 



An Account of some Experiments relative to the Passage 

 of Radiant Heat through Glass Screens ; by the Rev. Baden 

 Powell, MA. FRS. 



The object of this paper was to examine a question arising 

 from De la Roche's experiments, as to a particular case in which, 

 that experimenter supposed there must be a direct transmission 

 of simple radiant heat through glass. This case is that of a 

 second glass screen interposed between a first and the thermo- 

 meter, when M. De la Roche found the additional diminution 

 much less in proportion, than that occasioned by the first screen 

 on the total effect. He hence supposed the heat to have 

 acquired a property analogous to polarization, by which it was 

 enabled to penetrate the second screen without loss. 



The experiments here detailed were designed to examine, 

 first, whether this effect could be verified ; and, secondly, 

 whether, if so, it could be accounted for without introducing 



