'Royal Society. 223 



ratus being thus arranged^ he made the wire and the mercury alter- 

 nately positive and negative." Dr. Paris then gives an engraving 

 of the autograph account of the results, the substance of which is 

 as follows : — " When potash was introduced into a tube having a 

 platina wire attached to it — so — and fused into the tube so as to 

 be a conductor, i. e. so as to contain just water enough, though solid, 

 and inserted over mercury, when the platina was made negative, 

 no gas was formed, and the mercury became oxydated, and a small 

 quantity of the alkaligen vvas produced round the platina wire, as was 

 evident from its quick inflammatio^n by the action of water. When 

 the mercury was made the negative, gas wa.s developed in great quan- 

 tities from the positive wire, and none from the negative mercury, 

 and this proved to be pure oxygene. — A capital Experiment, 

 PBOViXG THK Decomposition of Potash." 



On the subject of this great discovery. Dr. Paris observes, " In 

 the progress of our ascent, it is refreshing to pause occasionally, and 

 to cast a glance at the horizon, which widens at every increase of 

 our elevation. By the decomposition of the alkalies and earths, 

 what an immense stride has been made in the investigation of na- 

 ture ! In sciences kindred to chemistry, the knowledge of the com- 

 position of these bodies, and the analogies arising from it, have 

 opened new views and led to the solution of many problems. In 

 geology, for instance, has it not shown, that agents may have ope- 

 rated in the formation of rocks and earths, which had not been pre- 

 viously known to exist ? It is evident that the metals of the earths 

 cannot remain at the surface of our globe ; but it is probable that 

 they may constitute a part of its interior ; and such an assumption 

 would ai once offer a plausible theory in explanation of the phaeno- 

 mena of volcanoes, the formation of lavas, and the excitement and 

 effects of subterranean heat, and might even lead to a general theory 

 in geology." 



[To be continued.] 



XXX. Proceedings of Learned Societies. 



ROYAL SOCIETY. 

 June 2nd — A PAPER was read, " On the Caves and Fissures in 

 -i*- the Western District of the Mendip Hills." By 

 the Rev. David Williams, A.M. F.G.S., Rector of the parishes of 

 Bleadon and Kingston-Seamoor, in the County of Somerset. Com- 

 municated by Davies Gilbert, Esq. V.P.R.S. 



The first cavern described in this paper is situated at Uphill, at 

 the very western extremity of tlie Mendip Hills. Its present en- 

 trance is about midway in a mural face of transition limestone, 

 about a hundred feet liigh. The fissure leading into it is nearly 

 vertical, and was discovered by some quarry-men casually inter- 

 secting it. Some bones and teeth being found there, the author was 

 induced to |)ursue the exploration of the lissurc j in the course of 

 which he discovered bones of the rhinoceros, hya-na, bear, ox, 

 horse, hog, fox, polecat, rat and mouse, and also of birds. The bones 



of 



