186 REPORT — 1861. 



Notice of a Volcanic Eruption on the Coast of Abessinia. 

 By Charles T. Beke, Ph.D., F.S.A., F.R.G.S. Sfc. 

 During tlie night of the 7th or morning of the 8th of May, 1861, a volcanic erup- 

 tion took place from Djebel Dubbeh, in about 13° 57' N. lat., and 4P 20' E. long., 

 accompanied by loud shocks resembling the discharge of artillery and immense 

 clouds of dust. The noises were distinctly heard both at Jlassowah and at Perim, 

 jjaces nearly 400 mUes apart, and the dust fell for several days over a vast extent 

 of the Red Sea, and on the coast of Aa-abia as far as the moimtain-range of Yemen. 

 At Edd, on the Abessinian coast, a day's jom-ney from Djebel Dubbeh, the dust 

 ■was knee-deep, and its fall dm-ing the first day caused total darkness. The erup- 

 tion continued at intervals for three or four days. There is no remembrance of any 

 previous eruption. Djebel Dubbeh is distant about 230 mUes, in a dii-ection almost 

 due north, from the gi-eat extinct volcano Aiyalu or Azalo, mentioned in Dr. Beke's 

 aper " On the Mountains forming the Eastern Side of the Basin of the Nile ; " and, 

 ike Aiyalu and also Kilimandjaro, it forms a portion of the mountain-system to 

 which he attributes the designation of the Mountains of the Moon*. 



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RemarTcs on the Glacial Movements tioticed in the Vicinity of Mount St. Elias, 

 ■ on the North-west Coast of America. By Admiral Sir E. Belcher, C.B., 

 P.B.A.8. 



Early in September 1837, Sir Edward's expedition ran down the coast of North 

 America, between ports Etches and Mulgi-ave, in order to fix the position and de- 

 termine the height of Mount St. Elias. 



The icebergs which hung about the coast were much lai'ger than those which 

 he had_ seen in Behring's Strait and northerly, or off the mouths of the fiords in 

 the -^-icinity of Port Etches. The icebergs presented a beautiful appearance. 



He (^Sir Edward) believed that in the upper valley of Icj^ Bay the lower bodies 

 of the ice were subject to slide, and that the entu-e substratum, as frequently foimd 

 within the Arctic Cu-cle, was composed of slippery mud. In ley Bay the appa- 

 rently descending ice, fi'om the mountains to the base, was in irregular broken 

 masses, which tumbled in confusion. The motion was clearly continuous. 



As to the causes which operated in producing the constant displacements of the 

 glacier, and the protrusion of the bergs to seaward, many theories had been pro- 

 posed. His (Sir Edward's) impression was that, whatever was the intensitj- of 

 cold under which congelation had taken place, the actual temperature due to the 

 ice was merely that of 32° Fahrenheit, and that self-registering thermometers, 

 roperly bmied in ice or snow, subject even to the very low temperature of 62° 5' 

 elow zero on the external skin of snow, only indicated the proper temperatui-e of 

 freezing water. Salt-water ice has a temperature or 28°. 



In the very high latitudes of 66° to 76° north, the snow on the siuface of the 

 snow-clad elevations funiished sufficient water to undermine the lower beds of snow- 

 ice, and bore a passage to the sea. However firm the crust might be in certain 

 positions, a fiu'ious ton-ent had been at work beneath. 



They were thus di-iven to the couclusion that the temperature of the earth must 

 in some degi-ee aid in keeping up a temperatiu-e sufficiently high to prevent the 

 congelation of the water hidden from light or the sun's raj's. The advance of vege- 

 tation was another proof, the gi-ouud-willow, saxifrages, and mayflower, and many 

 other plants, producing their shoots before light caused the immediate expansion 

 and colouring of the leaf. 



The earth's temperature, acting on the lower portions next to the soil, aided in 

 facilitating the travel of the slip of the snow-ice of which these glaciers were com- 

 posed to lower levels. In all ice-fomiations might be noticed, at the season which 

 followed the period of day frost or preceded the spring, a peculiar dryness, the re- 

 sult of evaporation of the supei-fluous water, attended by dense fogs. An ominous 

 cracking was then experienced, which had been misrepresented by some of the 

 first Arctic explorers as the breaking of the bolts of their vessels ; no bolt was ever 

 traced to have been so broken ! He imagined that the soU on which masses of eter- 



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* Various particulars respecting this eruption are gircn by Dr. Beke in The Times of- 

 the 20th and 2l8t June, 24th September,- and 16th October, lfc"61. 



