358 ANNUAL OF SCIENTIFIC DISCOVERY. 



ON THE SILURIAN SYSTEM. 



At a recent meeting of the Geological Society, London, Sir R. I. Mur- 

 clieson, in a paper on the Silurian rocks of Scandinavia and Russia, took oc- 

 casion to point out the extent of the great northern Silurian basin. Begin- 

 ning with the comparatively small fragments of this great deposit in the 

 British Isles, the Silurian rocks may be traced across the main land of 

 Sweden, through the islands of Gland and Gothland, to the southern shores 

 of the Gulf of Finland. Here they extend through the province of Esthovia, 

 south of Revel and Narva, towards St. Petersburg. From the government 

 of St. Petersburg, the range taking a direction from W.S.'W. to E.N.E., 

 is lost beneath the vast deposits of Lakes Ladoga and Onega. It re-ap- 

 pears, however, on the flanks of the great Ural chain, and traversing Si- 

 beria, is again found in North America, covering a vast extent of Canada, 

 occupying in detached masses more than a thousand miles in width from 

 Canada to the state of Alabama, and extending westward from New York 

 to the furthest western prairies. 



"With reference to the European portion of this great Silurian area, the 

 northern basin of the British Isles, Scandinavia, and Russia, appears to be 

 separated by marked paleontological characters from the Silurian rocks of 

 Southern Europe, as they exist in France, Spain, and Bohemia. In limited 

 areas, such as that of the British Isles, the evidence derived from fossil re- 

 mains was much more restricted than where larger areas were examined. 

 For instance, throughout the whole range of the British Silurian rocks, 

 definite species of mollusca, Crustacea, and corals, were found to charac- 

 terize certain beds, but when the whole northern area of the Silurian rocks 

 is examined, these species are found to range upwards and downwards into 

 other beds, and thus the whole formation is much more converted into one 

 unbroken series than would be justified from the examination of the British 

 Isles alone. Sir Roderick quoted many examples of upper and middle 

 Silurian fossils occurring very low down in the rocks of Scandinavia, and 

 thus supported his views so often and so long ago expressed that one un- 

 broken chain of life extended from the top of the Silurian series down to the 

 base of the Llandeilo flags and Lingula beds. He held it, therefore, im-- 

 possible to draw any line of separation between the Silurian rocks and those 

 which had been called Cambrian, unless that line be drawn at the base of 

 the Lingula flags. 



HEIGHT OF NORTH CAROLINA MOUNTAINS. 



The lofty peaks of western North Carolina were barometrically measured 

 by Prof. Guyot, in July, 1856, with the following results. r J hesc twelve 

 summits are all higher than Mount Washington in New Hampshire, which, 

 according to Professor Bache's survey, in 6,285 feet in height. 



1. Clingman's Peak, 6,701 feet; 2. Guyot's Peak (or Balsam Cone), 

 6,661 feet; 3. Sandoz Knob, 6,612 feet; 4. Hairy Bear, 6,597 feet; 5. Cat- 

 tail Peak, 6,595 feet; 6. Gibbe's Peak, 6,586 feet; 7. Mitchell's Peak, 6,576 



