Dr. E. L. Moss. Observations on Arctic Sea-water and Ice. 549 



— 37 0, 4 C, No. 1 had lost an additional "9, and No. 2 gained an 

 additional "6. 



Admiral Wrangell, in describing the heavy ice gronnded along the 

 northern shores of Siberia, accounts for both its thickness and its 

 stratification by the sliding one upon another of thinner floes.* 

 Admiral Belcher referred some of the great ice mases in Wellington 

 Channel to the same canse,f but the stratification of the floes met with 

 by our expedition cannot be thus accounted for. The behaviour of 

 strata overlying an old surface- dome, best shown in the accompanying 

 little diagram (fig. 1) — a copy of a pencil sketch made from nature — 

 is utterly inconsistent with the sliding-up hypothesis. 



Fig. 1. 



The subject of this sketch afforded the only instance of stratifica- 

 tion overlying a " blue dome " seen by me. Any deviations from the 

 horizontal and parallel were in fact extremely rare, and one of the 

 first convictions forced upon me by the facts of the stratification was 

 that the floes which showed it could not have been formed in such a 

 region of chaotic disturbance as lay about us. 



Massive floes drifted from the westward into the channels of the 

 Parry group, or floating southward in Spitzbergen seas, have made 

 arctic travellers familiar with the glassy " blue tops " or domes of ice 

 standing up through the surface snows. J The upper part of many of 

 our grounded floes exhibited such domes in section, and in every case 

 the wavy outline cut through the horizontal strata. The larger mounds 

 often occurring in miniature mountain ranges on heavy floes are not to 

 be confounded with " blue domes." They occur along ancient lines of 

 fissure, and are simply old hummocks rounded off by snowdrift. 



The occurrence of air-carried dust on the surface of both glacier and 



* Wrangell's " Siberian Journey," edited by Sabine, Appendix, p. 393. 

 f Belcber's " Last of Arctic Voyages," vol. i, p. 101. 



X The journal of Lieutenant Mecbani of the " Resolute " gives a typical descrip- 

 tion and sketch, of them. — Pari. Reports, 1855, vol. xxv, p. 694. 



