200 FROZEN WELL. 



According to Sir II. I. Murcliison it was the elevation of Siberia, at the close of the ter- 

 tiary period, that changed its climate so that elephants, tigers and other tropical animals 

 could no longer live there. But their bones, and in one or two instances their undecaycd 

 carcasses have been preserved in the frozen soil. We have some doubts whether such an 

 elevation of the land, which appears to have been slow and not paroxysmal, can explain 

 some of the facts respecting the frozen ground. At the depth of 70 feet there was found 

 an alternation of layers of ice and frozen soil. How this ice could have been formed by 

 the mere elevation of the land we do not see; but if that were slowly sinking and a deposit 

 of soil was going on, such alternations with ice might occur, as they now do sometimes in 

 arctic regions. Indeed we find it difficult to conceive how the soil and rocks even in a 

 Siberian climate, as it now is, could have frozen to the enormous depth of nearly 400 feet, 

 unless it was done while the strata were in a course of deposition near the surface, and 

 were afterwards sunk to their present levels. The frozen animals by this view must have 

 been encased near the close of this process; yet these are regarded as being as old at least 

 as the drift period ; so that we may be sure that this great mass of frozen soil is at least 

 as old as the drift period. 



In attempting to give some probable theory of the phenomena at Brandon, \ve shall 

 approach the subject by a few preliminary positions. 



1. We regard the cases at Ware and Owego as essentially like that at Brandon, and to 

 be explained in the same manner. 



2. The phenomena most probably have a connection with a gravelly and sandy soil, and 

 hence we should make the character of such soil an element in our explanations. 



3. As the frozen deposit is in such a soil, the idea is precluded that the congelation is 

 the result of chemical re-agents. At Brandon, however, in describing the first excavation 

 made by the Boston Natural History Society, Mr. Higgins describes an arrangement of 

 the sand and pebbles which he calls "crystallized limestone upon the cobble stones, which 

 looked like frost, and this substance upon the lower side of the stone." We think this 

 was the effect of frost ; for we have often seen it in the spring among pebbles and sand 

 that had been frozen during the winter. The crystallization of the ice caused the finer 

 materials to assume a correspondent form, and their semi-fluid condition, especially if in 

 part comminuted limestone, would give room for enough play of chemical affinities to pro- 

 duce a slight cementation, but not enough to explain the refrigeration of the mass. These 

 facts, however, do show the greater extent of the congealed state of the materials formerly 

 than at present ; for in this well, 29 feet deep, no frozen soil was found. 



4. The fact that currents of air occur in probably all the frost caverns of the eastern 

 and western continents as described above, awakens the presumption that they may exist, 

 even if very feeble, in the porous soil of the frozen wells. 



5. For similar reasons a still stronger presumption exists, that evaporation is perhaps 

 the most efficient agent concerned in the preservation, if not the productioa, of the frozen 

 masses in which the wells are situated. 



6. The temperature in the wells is strongly affected by the temperature of the air at the 

 surface. In winter the cold is much more intense than in summer. 



The subject presents two leading inquiries : 1. When and by what agency was the 



