5o8 



NATURE 



[April 29, 1875 



centre of the earth, the first external contact occurred on 

 December 6, at ijh. 47-8m. Greenwich mean time, at 35° 

 from the north point of the sun's disc towards E. for direct 

 image, and the last external contact at l8h. 26-8in. about 

 4° towards W. At Paris the final contact took place at 

 i8h. 5o-3m. local mean time, but the sun did not rise till 

 igh. 39m. ; the planet therefore had left his disc less than 

 fifty minutes before he was on the horizon of Paris. 



ARCTIC GEOLOGY* 

 IV. 



Vardo Island, f at the end of a long promontory in the 

 polar basin, is described by Mr. Campbell, of Islay, J as 

 consisting of metamorphic slates, dipping at 45°, and 

 striking with the hollows and ridges north and south, 

 ground into shape by ice, but since submerged and wave- 

 worn ; drifts packed and rolled by the sea are left in a 

 grass-grown raised beach at 60 feet, a peat-covered beach 

 at 100 feet, and rolled stones occur on the summit 

 level of the island, 220 feet above the sea, resting on 

 red sandstones, with fossil markings in concentric 

 rings. At 30 feet above the sea occurred a " storm 

 beach," with large and sub-angular stones, sweeping in a 

 crescent round the bay, the fortress of Vardo, and the 

 church of Vadso. He describes it as built on coral 

 sand, and refers to the warm equatorial current affecting 

 the climate in the polar basin to lat. 80° in Spitzberijen, 

 and to long. 66^ E. in Novaya Zemlya, which enables a 

 luxuriant vegetation to live on the shore at Yeredik, about 

 70° N., in spite of the winter's darkness. 



The most northern island of Novaya Zemlya has been 

 called Castanjeno by Capt, Mack, from the " Mimosa 

 beans " or chestnuts found there, which tropical brown nuts 

 in Spitzbergen reach 20" E. ; § but Mr. Lamont considers 

 the large quantities of drift wood found on that coast to be 

 derived from pines (Alucs excclsa) that have grown on the 

 banks of the large Siberian rivers ;1| and states that when 

 wood occurs inland it is associated with bones of whales. 

 He therefore does not agree with Lord Dufferin that 

 it is brought to Spitzbergen by the Gulf Stream,^ which 

 Mr. Lamont states has no influence north and east of 

 Black Point and the Thousand Isles, even during June, 

 July, and August, while during the winter months ice-laden 

 currents sweep round Spitzbergen on both sides from the 

 north, and bear back the equatorial current, and envelop 

 the entire island with a wall of ice. 



These rapid changes of direction of currents, with 

 accompanying marked alteration of climate, appear to 

 bear a close analogy to those which must have obtained 

 in South Britain when the alternating beds of boulder- 

 clay and sands and gravels were being deposited, clay 

 with scratched stones during the colder intervals, and 

 sands during the warmer episodes, when the waves were 

 fretting coasts unprotected by ice. 



Icebergs appear to have ground the surface of the 

 rudely columnar trap-rocks of the Thousand Islands, 

 which are covered with countless smoothed and rounded 

 boulders of the local trap, and of red granite derived 

 from the centre of Spitzbergen, forty miles distant. 



In one of the cluster of islands off the coast at Black 

 Point is a channel 100 yards long, three or four feet wide, 

 and four deep, running N.E. and S.W., excavated in the 

 boulders, which Mr. Lamont believes to have been produced 

 by the passage of an iceberg, when the land stood lower 

 than at present. The power of bergs to groove and scoop 

 out hollows has been denied, and it is to be hoped that the 



* Continued from p. 494. 



+ In the following notes on Spitzbergen and other neighbouring islands, 

 only those points have been touched on as have a direct bearing on the 

 geology of the area already described. 



I Quar. Jour. Geol Soc. , vol. xxx. p. 455 ; 1874. 



§ *' Frost and Fire," by J. F. Campbell, vol. t. p. 483. 



II '* Seasons with the Sea Horses." London, i86t. 

 II " Letters from High Latitudes." (London.) 



officers of the Arctic Expedition will have opportunities 

 of ascertaining what the usual character of the bottom 

 portion of a berg is, how far it is capable of grooving rocks 

 and excavating hollows in soft sea beds, with or without 

 coming to rest. 



Separated from the great glacier of Deeva Bay by two 

 miles of sea covered with fast ice, is a terminal moraine 

 of mud, 3i miles long, 200 to 400 yards broad, and 20 to 

 30 feet high, on the top of which grow Arctic plan'.s. 

 Observations as to what extent glaciers can extend into 

 the sea, and push moraines before them without breaking 

 off into bergs, would have great interest, for in this 

 instance the sea must have been deeper during the 

 maximum size of the glacier than now, as bones of whales 

 occur at heights of more than forty feet above the present 

 sea level. 



One of the three large glaciers that protrude into the 

 sea between Black Point and Ryk-Yse Islands has a sea 

 front of thirty miles, sweeping in three great arcs, five 

 miles beyond the coast line, terminating in a precipitous 

 wall from 20 to 100 feet in height, from which bergs 

 are constantly tumbhng into the sea, carrying stone and 

 large quantities of clay and stones seawards. The posi- 

 tion of the melting area of such bergs as these, and con- 

 sequent deposition of erratic material, is a point of great 

 interest in attempting to unravel the British glacial 

 phenomena. 



Prof Wyville Thomson, dredging on the edge of the 

 southern ice pick, brought up fine sand and greyish mud, 

 with small pebbles of quartz, felspar, and small fragments 

 of mica-slate, gneiss, and granite, derived from the 

 melting of icebergs found in lat. 65° or 64° S., which 

 represents their melting area, while further south in 200 

 to 250 fathoms of water, in which they first commence to 

 float, land debris is much rarer ; at the surface of the 

 water in the melting area, Globigoiiia and diatoms are 

 numerous, but do not form a deposit at the bottom, owing 

 to the deposition of silt obliterating them. 



Recent Elevation of Spitzberi^en.— YxQva the obser- 

 vations of Mr. Lamont it may be inferred that during the 

 past 400 years Spitzbergen has been rising at the rate of 

 thirteen feet per century. 



Bear Island (lat. 74° 30' N.) — From the plants and spe- 

 cimens collected by Professors Nordenskjbld and Malm- 

 gren, the following classification of the rocks of the island 

 has been established* :-- 



Millstone Grit. — Siliceous schists. 



MoLJNTAiN Limestone Stage. — Proanctus limestone, 

 spirifcr limestone with gypsum, resting on Cyathophyl- 

 /««-bearing limestone and dolerite, possibly the equiva- 

 lent of the Carboniferous shale with Cyathophyllum of the 

 south of Ireland. 



Ursa Stage of O. Heer. — Sandstones, with shale and 

 coal-seams. All the beds contain plants. 



Devonian.' — Russian Island limestone, red shale. 



The Russian Island limestone, which spreads over so 

 large an area in Spitzbergen, contains no determinable 

 fossils, and, like the shales beneath it, is of doubtful geolo- 

 gical age, probably, as suggested by Nordenskjold, belong- 

 ing to the Devonian. No true coal measures are present 

 either in Spitzbergen or Bear Island. 



The " Ursa Stage " Prof. Heer correlates with the 

 Kiltorkan beds in Ireland, the Greywacke of the Vosges 

 and southern Black Forest, and the Spirifera Verneuilii 

 shales of Ai.x, and the sandstones of Parry and Melville 

 Islands in the Arctic Archipelago ; and from the marked 

 absence of Devonian and coal-measures species, regards 

 the stage as of Lower Carboniferous age, the base of 

 which he considered to be beneath the yellow sand- 

 stones ; but Sir Charles Lyell, from the fact that these 

 sandstones at Dura Den, in Fife, and in the co. Cork, 

 contain the exclusively Devonian fish Asterolepis and 

 Glyptolepis, believed these deposits to be Devonian, which 



* Quar. Journ. Geol. Soc, vol. xxviii. p. i6i. (Read Nov. 9, 1868.) 



