458 Geological Society. 



must be gratifying to all calculous patients, as furnishing 

 them with some weli-grounded hopes of a speedy and cer- 

 tain remeclv. The use of muriatic and carbonic acids con- 

 tinued for some months effected permanent cures, even 

 where the patients had been previously cut for the stone. 

 The Society then adjourned over the Whitsuntide festival 

 till 



June 17. — The right hon. Earl of Morton in the chair. 

 A letter from Mr. Exiey of Bristol to the President, and 

 by him communicated to the Society, was read, on the 

 Theories of Electricity and the difficulties attached to them. 

 The author prefers the Franklinian theory to all others, and 

 endeavoured to explain those parts of it which are least 

 compatible with the known facts. He defined the terms 

 plus and minus or positive and negative electricity some- 

 what in the usual manner, assumed thiit attraction and re- 

 pulsion depend on the similarity of electric conditions, and 

 showed why non-electric are good conductors, and vice 

 vei'sa. He purposes pursuing the inquiry. 



June i'4. Part of a paper by Sir E. Home was read, 

 containing additional remarks to a former paper on the 

 anatomy of the Squalus maximus. The most remarkable 

 fact was the existence of a small fin between the anus and 

 the tail, which was overlooked in his preceding observa- 

 tions, and which contributed to lead naturalists into serious 

 errors. Sir E. entered into stmie details, which were illus- 

 trated by drawings, on the general structure of this squalus, 

 which was thirty feet long, and that of a dog-fish of only 

 three feet. The inquiry respeciing the supply of air to / 

 fishes was also touched on, and Sir E. made some experi- 

 ments on the effect of pressure of water at a considerable 

 depth, and particularly in a well 680 feet below the surface 

 of the Thames, belonging to Mr. Coutts. The object was 

 to prove that the atmospheric air in water at that depth 

 was the same as in water near the surface. Sir E. made 

 some remarks accompanied with speculations on the ex- 

 panding and contracting powers of the vessels in the gills 

 of sharks, which enaljled them to sustain the pressure of 

 water at 150 fathoms below the surface. 



GEOLOGICAL SOCIETY. 



June 4. — The President in the chair. 



The Duke of Devonshire ; 



John Whishaw, Esq. of New Square, Lincoln's Inn j 



Henry Drummond, Esq. ; 



Charles 



