736 APPENDIX 



conditions excellent — they probably would. For the presence or absence 

 of seals beneath their feet they would care not at all. 



But for those who count on getting their food and fuel as they go, 

 these ice deserts are the one source of gravest concern. We cannot tell 

 in advance for certain where we shall find them, for we can reason only 

 on the basis of what we know and in the Arctic there are still many 

 things unknown. When we come to the edge of such deserts we can 

 guess only very roughly at their extent or in what direction the diameter 

 will be least. They are, in the system of "living by forage," the most 

 serious source of danger, although the mere understanding of their 

 existence lessens the danger. 



