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FOURTEENTH ORDINARY MEETING, 

 Held at the Eoyal Institution, on the 18tli May, 1857, 

 THOMAS INMAN, Esq., M.D., President, iu the Chair. 



The following were elected Ordinary Members : — 

 Francis HEywooD, Esq. 

 James W. Whitehead. 



Dr. Thomson exhibited the raw material and rug made from the skins 

 of the Aviru, a South American animal, the property of Mr. Danson. 

 He referred to the importance of this wool, and its cheapness in the 

 imported form. 



Mr. Bterley exhibited a specimen of the Mya arenaria, and also the 

 shell of a common cockle, which was interesting as an instance of 

 animal sagacity in self-defence. The shell had been bored by a 

 haccinum, and the cockle, on feeling itself attacked, or annoyed by the 

 sand which entered at the hole, had retired to the middle of the shell 

 and thrown out a sort of diaphragm, which formed a complete barrier 

 between it and the outer aperture, the intermediate space being filled 

 with sand. 



The paper for the evening was then read. 



AN ACCOUNT OF SOME OF THE VOLCANOES OF ITALY. 

 By THOMAS INMAN, Esq., M.D., Peesident. 



Aided by diagrams, he entered with considerable minuteness, and in 

 his usual lucid and interesting manuer, into the history and topography 

 of his subject, concluding with the following observations as to the 

 causes of volcanic action : — 



We find that there are two theories, the physical and the chemical; 

 both of them extremely ingenious, but evidently not equally tenable. 

 The one supposes the eruption to be literally a breaking through the 

 outer crust of the earth of that central fii-e which is supposed to be 

 constantly burning ; but in addition to the many objections that have 

 been urged to this hypothesis, there seem two or three prima facie 

 considerations against it of great weiglit. It is, in the first place, 

 difficult to understand how, when a vent has been established, having 

 an area of some four, five, or six hundred miles, that that vent 

 should ever become entirely closed, and a number of small ones 

 replace it with an aggregate area of only ten or twenty. We have, 

 for example, seen in Italy tho vast size of her extinct craters, and, 



