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THE GEOLOGIST. 



fell on it^ although at the present time it appears probable that 7 00 

 fall annually ? " To which Humboldt has replied, that problematical 

 nickeliferous masses of native iron have been found in northern Asia, 

 at the gold-washing establishment of Petropawlowsk, eighty miles 

 south-east of Knsnezk, imbedded thirty-one feet in the ground; and 

 more recently in the Western Carpathians (the mountain-chain of 

 Magura, at Szlaniez), in both of which cases they are remarkably like 

 meteoric stones."^ 



The Governor of the Island of Reunion (Bourbon), in a despatch of 

 the 8th December last, says : — " The volcano of this island is now in 

 full eruption. Since last week a torrent of burning lava has been 

 seen flowing towards the sea, and all communication with the Arron- 

 dissement du Vent has been cut off ; the lava having crossed the high 

 road for an extent of 400 yards, and to the depth of from nine to 

 twelve feet." The flow of lava reached the sea on the 9th. This 

 volcano of Bourbon is the most active of all those existing in the 

 southern hemisphere, between the west coast of New Holland and the 

 east coast of America. The greater part of the island, particularly the 

 western portion and the interior, is basaltic. Recent veius of basalt, 

 with little admixture of olivine, run through the older rock, which 

 abounds in olivine ; beds of lignite are also enclosed in the basalt. 



The summit of the volcano of Bourbon, which Hubert describes as 

 emitting nearly every year two streams of lava, which frequently 

 extend to the sea, is eight thousand feet high. It exhibits several 

 cones of eruption, which have received distinct names, and which 

 alternately send forth eruptions. Eruptions from the summit are 

 not frequent. The lavas contain glassy felspar, and are therefore 

 rather trachytic than basaltic. The ashes frequently contain olivine 

 in long fine threads, like that produced by the volcano of Owhyhee. 

 A violent eruption of these glassy threads, covering the whole island of 

 Bourbon, occurred in the year 1821.t 



M. Fleurion, professor in one of the Imperial Schools of Agriculture, 

 announces to the Paris Academy of Sciences, that, having noted for 

 some time past the variations of temperature in the air, and at a 

 depth of two metres beneath the surface of the soil, he has found by 

 comparing them, that the temperature of the earth at this depth is 

 invariably higher by two-tenths than that of the air at the surface. 

 It is probable that a slip of the pen has caused the author to write 

 down two-tenths instead of one-tenth. For, taking two metres to be 

 (in round numbers) equal to six feet, and admitting an increase of one 

 degree Fahr. for every fifty-four feet (Euglish) in depth, we have : 

 54 ft, : 6 ft. = 1 ° Fahr. : x. 



X = = 0.111, or -jL. 



* Mr. E. W. Binney has described the occiuTence of three probably meteoric 

 stones in the coal-measures of Lancashire. — Transact. Liter. Fhilos, Soc. of 

 Manchester, vol. IX. — Ed. Geol. 



t For an account of a recent discovery of gold in the island of Bourbon, see 

 my article m The Geologist for March, 185S.— T. L, P, 



