76 Calculus in iJte Bladder. 



chemical nature of fliuir-spar. — Captain Lasky also read a pa- 

 per on the Pinna ingens or Fennanl. From his observations it 

 appears, that the Pinna ingens of Montagu, Pinna boreahs of 

 Stewart, and Pinna ingens of the Linnasan Transactions, are 

 the same species, and identical with the Pinna ingens of Pen- 

 nant. — At the same mtetin:i, Charles Anderaon, esq. read 

 somcobs( rviitions on the geognosy of the island of Inctikciih, 

 in the Frith of F^rih. It appears from the interesting details 

 which he conmnmicated, that the whole island is composed 

 of rocks belonging to the independent coal formation ; and 

 that the green- stone which there occurs, is traversed by true 

 veins iiiled with iipiarfz, chalcedony, calcspar, &c. ; and also 

 contains numerous contemporaneous veins of different kinds. 

 Mr. Anderson intimated his intention of laying before the 

 Society, at a future meeting, a more particular description 

 of the island, ijlustraled by drawings and a series of speci- 

 mens. 



XV. Intelligence and Miscellaneous Articles. 



CALCULUS IN THE BLADDER. 



JVl. VuRZER, a French chemist, has published the follow- 

 ing analysis in support of Messrs. Fourcroy and Vauque- 

 lin's discovery of silex in urinary concretions* : 



" I received the calculus, of which the following is the 

 analysis, from M. Michatlis, who extracted it by an opera- 

 tion from a patient. 



- *' Physical Properties. — It was nearly oval, but a little 

 compressed ; brown ex'ernallv, and of a yellowish white in- 

 ternally. It weighed exactly 870 grains ; its specific gravity 

 was 1 'S'S ; its surface was irregular and uneven. It was of 

 the consistence of hard chalk, was entirely without a nu- 

 cleus, and was composed of layers. 



" Chemical Examination — 1. I macerated 300 grains of 

 this concretion (after having pulverised them) for two days 

 in distilled water, at a temperature of 12° (Reaumur). I 

 |ben filtered, The colourless liquor presented by the reagents 



• from /lanales ds Ckimie, torn. Ix. p. 310. 



the 



