General Science. 183 



mines near Harzgerode, in the south-east part of that mountain, so inte- 

 resting to the geologist, show that the greenstone and porphyry are raised 

 from the interior of the earth. Baron Leopold Von Buch is of the same 

 opinion, with regard to the granite of the Hartz and the porphyry in the 

 neighbourhood of Ilfeld. 



32. Geological Map of Germany in 42 sections. — This great map is pub- 

 lished by Simon Shropp and Company in Berlin, under the direction of 

 the Baron Leopold Von Buch. The twelve sections now published con- 

 tain I, the title-page ; 2, the table of colours ; 3, the review of the sections ; 

 4, -the country of Odensee ; 5, of Copenhagen ; 6. of Lincoln ; 7, of liOn- 

 don; 8, of Boulogne; 9, of Munich; 10, of Salzburgh; 11, of Milan ; 12, of 

 Triest. 



IV. GENERAL SCIENCE. 



33. Discovery of a remarkable structure in the knee-joint of the 

 Echidna hystrix of Australasia. By Mr F. J. Knox. — We confine 

 ourselves, at the request of Mr Knox, to a very brief notice of this 

 remarkable structure which he has discovered to prevail in the knee-joint 

 of the Echidna, and to a certain extent also in that of the Ornithoryn' 

 chus paradoxus, Blumenbach ; but the notice, though short, will be intel- 

 ligible to all anatomists acquainted with the structure of the human knee- 

 joint. That peculiar structure in the human knee-joint, usually known 

 by the name of the ligamentum adiposum, constitutes, in the corresponding 

 joint of the Echidna, a broad double membrane, dividing the joint into two 

 perfectly distinct synovial cavities. In the superior of these cavities, the 

 articular surfaces are the patella and a portion of the condyles of the fe- 

 mur ; in the lower cavity the articular surfaces are the inferior half of the 

 same condyles and the upper surface of the tibia. 



A full account of this discovery, with explanatory drawings, has been 

 transmitted some months ago to the Royal Society. 



34. Hydrogen Gas from Salt Mines employed for producing light, and 

 for fuel. — In the salt mine of Gottesgabe at Rheine, in the county of Teck- 



lenbourg, there has issued for sixty years from one of the pits, which has 

 on this account been called the Pit of the Wind, a continued current of 

 inflammable gas. The same gas is produced in other parts of the mines. 

 M. Roeders, the inspector of the salt mines, has used this gas for two years 

 not only as a light but as fuel for all the purposes of cookery. He collects 

 it in pits that are no longer worked, and conveys it in tubes to the house. 

 It burns with a white and brilliant flame. Its density is about 0.66. It 

 contains only traces of carbonic acid and sulphuretteel hydrogen, and there- 

 fore should consist of carbonated hydrogen and olefiant gas. 



35. Natural Gas Lights at Fredonia.— This village, on the shores of Lake 

 Erie, is lighted every night by inflammable gas from the burning springs, 

 as they are called, in its vicinity. Captain Hall has visited this village and 

 will no doubt give us a good account of it on his return. 



