194 Saentrfic Intelligence. — Geology. 



12. Relative Position of Granular Rocks. — Serpentine, dio- 

 rite, angite rocks, auriferous porphyry, augiiic porphyry, and 

 granite of Predazzo, traverse primitive slates, transition rocks, 

 and secondary and tertiary deposites ; and the granite of Baveno; 

 and of Mettelwakl, in the Tyrol^ and the sienite of Skye, tra- 

 verse Has Hmestone. 



13. Silver Mines of Kongsherg. — Within a few years, the 

 working of the former famous silver mines of Kongsberg in 

 Norway have been resumed, and with great profit : thus, during 

 the month of April of last year (1831), 865 marks and 16 loth 

 of silver were obtained ; and, in the first week of May of the 

 same year, 245 marks 10^ loth, of which the Armengrube alone 

 afforded 219 marks 1.2 loth. 



MINERALOGY. 



14. Analyses of Limestones of Barjarg and Closchnrn, ifi 

 Dumfriesshire; by William Copland, Esq. — At Barjarg 

 Quarry the limestone contains about 56 per cent, of carbonate of 

 lime, and 35 per cent, of carbonate of magnesia. At Closeburn 

 Quarry, the upper bed of limestone is nearly identical with that 

 of Barjarg ; but there is a lower bed, which is very different in 

 its composition, as it contains from 80 to 90 per cent, of carbo- 

 nate of lime, but no magnesia ; at least I was not able to detect 

 any in any of the specimens which I analyzed. 



15. Analyses of Chabasites^ by Dr Em. Hoffmann. — Cha^ 

 basite from Riebendorfel, near to Aussig, in Bohemia. Speci- 

 fic gravity at + T,l R. = 2.127. Silica, 48.18. Alumina, 

 1927. Lime, 9-65. Natron, 1.54-. Potash, 0.21. Water, 

 21.10: =: 99.95. — Chabasite from the valley of Fassa. Specific 

 gravity at + 8°.3 R. = 2.112. Silica, 48.63. Alumina, 19.52, 

 Lime, 10.22. Natron, 0.56. Potash, 0.28. Water, 20.70: 

 =: 99.91. — Chabasite from Parsborough. Specific gravity at 

 -h 7° 6 R. = 2.075. Silica, 51.46. Alumina, 1 7.65. Lime, 

 8.91. Natron, 1.09. Potash, 0.17. Oxide of Iron, 0.85. 

 Water, 19.66 : = 99.79. 



16. Analyses of Arsenical Pyrites, by Dr Hoffrnann. — 

 Arsenical Pyrites from Reichenstein, in Silesia — is the arseni- 

 kalkies of Weiss ; axotomous arsenical pyrites of Mohs. Sul- 

 phur, 1.94. Arsenic, 65.99. Iron, 28 06. Serpentine, 2.17: 



