Progress of Foreign Svieiice. 329 



3. A variety of malacolite from Norway (sahlite,) sp. gr. 

 3.1, analyzed by Count Trolle, gave silica 57.4, lime 23.1, 

 magnesia 16.74, loss 2.76, in 100 parts. He considers it as 

 represented by the formula C S=+ M S^; that is, abi-silicate 

 of lime associated with a bi-silicate of magnesia. 



4, Analyses of some northern minerals, by C. d'Ohsson, 

 Swedish ambassador at the Hague. They were undertaken at 

 the invitation of Berzelius, and verified by him. 



Garnet of Broddbo, sp. gr. 4.25, It fuses into a black glo- 

 bule before the blow-pipe. It consists of silica 39, alumina 

 14.3, protoxide of iron 15.44, protoxide of manganese 27.9, 

 tungstate of zinc 0.5, silicate of zinc 0.5, loss 2.36 in 100. He 

 represents its atomic constitution, on Berzelius's plan, by 

 FS= +2MgS +2 AS. ; that is, 1 atom of bi-silicate of iron, 

 + 2 atoms silicate of manganese, +2 atoms silicate of alu- 

 mina. 



Malacolite of Bjornmyresveden, sp. gr. 3.331 . It consists of 

 silica 57.28, lime 24.88, magnesia 9.12, protoxide of iron 6.04, 

 protoxide of manganese 0.72, loss 1.96; or, M S »+2 C S\ 

 viewing the iron and manganese as accidental associates. 



A new mineral from Pargas, called Chondrodite (granular,) 

 colour wine-yellow, occurs in grains about the size of a pin- 

 head, fracture small conchoidai, lustre between waxy and vitre- 

 ous, scratches glass, sp. gr. 3.18. Dissolves in neither nitric 

 nor muriatic acid ; infusible before the blow-pipe, but becomes 

 darker coloured ; with soda it fuses into a bright green slag. 

 With borax it readily melts, with intumescence, into a bright 

 greenish-yellow glass. Its constituents are, silica 38.0, mag- 

 nesia 54, oxide of iron 5.1, alumina 1.5, potash 0.86, manga- 

 nese a trace, loss 0.54. Viewing the iron and the latter ar- 

 ticles as unessential, M. d'Ohsson thinks its constitution may 

 be represented by the simple formula M S, a silicate of magne- 

 sia. It occurs near Pargas, in Finland, interspersed in gra- 

 nular limestone. — Schweigger's Journal, Dec. 1820. 



Examination of a inetcoric stone which fell in Courland, in 

 the circle of Diinaberg, on the 12th July, 1820, by Theodore 

 Von Grotthus. Between five and six o'clock in the evening, a fire- 

 ball apparently as large as the full moon, was seen moving slowly 

 from south to north. It seemed to burn with a reddish flame, 

 which also followed it, like the train of a comet, leaving in the 

 distance spiral clouds, which moved very slowly, and then melted 

 in air. After this meteor had described in the heavens an arch 

 of nearly 100°, it became extinguished. In less than a minute 

 afterwards there resounded from the reerion where the fire-ball 

 had vanished, a noise resembling, first, three rapid disciiarges 

 of great guns; then a fire of musketry; and finally, a con- 

 tinuous rolling like rhunder peals. At the same time, a stone 

 fell from the air, 3i German miles from the country palace of 



Vol. XII. Z 



