350 Scientific Intelligence — Geology. 



lar deposits elsewhere, and for banks and shoals coniposed of the 

 coralline detritus in the Indian Seas." Since this was written, 

 Lieut. Davis has given the American Academy his views on what 

 may be termed Tidal Geology, and the consequent formation of 

 shoals, banks, bars, beaches, nooks, and sea-walls ; and he has suc- 

 ceeded in tracing the effects of great causes through all their myste- 

 rious phases, with the cautious observation and inductive experiment 

 which science demands. — (^Journal of the Royal Geographical So- 

 ciety of London, vol. xxi., p. xcii.) 



5. Different Gneiss Formations. — Many years ago we observed in 

 our Highlands, gneiss associated with conglomerate, and great veins 

 of gneiss traversing gneiss. These facts have been verefied by the 

 discovery of similar phenomena in other countries. In this note we 

 have only space for the following. Gneiss is now divided into the 

 following formations : 1. Primary gneiss, that associated with cer- 

 tain granites, and forming; the fundamental or oldest formation of the 

 crust of the earth ; 2. Transition gneiss, that which rests upon tran- 

 sition rocks, as greywacke, clay-slate, and old red sandstone, and 

 even alternates with them ; 3. Secondary gneiss. This formation 

 rests upon lias, and is well seen in Switzerland. We have no inti- 

 mation that gneiss has been met in the tertiary class. 



6. Pseudomorphic Nature of Serpentine. — ^Many years ago Stef- 

 fens and Jameson noticed the gradual transitions from trap to ser- 

 pentine, as observed in Germany and Scotland. Very lately the 

 celebrated George Rose of Berlin has illustrated this important view 

 in a very interesting manner. — (T^eonhard and Bronn^s Jahrhuch, 

 6 Heft, 1851.) 



7. Cause of the Thermal Waters in Western Asia-Minor. — The 

 cause of the abundance of warm springs in this quarter of the globe, 

 in all formations from the alluvial to the oldest rocks, is doubtless 

 owing to the extensive igneous action within no great depth beneath 

 the surface of the country ; a fact evinced by the frequency of earth- 

 quakes, but more especially by their extent ; for they almost inva- 

 riably extend from one end of it to the other, as well as to the neigh- 

 bouring islands. 



Neither time nor change of government has contributed so much 

 to the destruction of the hundreds of magnificent cities which once 

 covered this country, as the desolating influence of the earthquake ; 

 and many are the cities that now exist, which have been prostrated 

 over and over again, and rebuilt, each time in diminished splendour, 

 until at last they are little better than collections of huts, when con- 

 trasted with their original condition. All the country at the pre- 

 sent day seems to be as much subject to them as formerly. 



The only part of Western Asia-Minor where phenomena are seen 

 strictly analogous to those of active volcanoes, is in the Catacecau- 

 m,ene or Burnt district, situated in Lydia, about one hundred miles 

 east of Smyrna. Numbers of volcanic cones exist in the neighbour- 



