PORMING ICE. 383 
rents and winds, and the final depravation of crystal- 
line structure, are marshaled with forces of upheaval 
and depression, the synclinal and anticlinal axes which 
characterize the splendid dynamics of ice in motion. 
I intended, when I hegan to arrange this narra- 
tive, to offer my ice-notes as a contribution to the 
Smithsonian publications. But a new duty is before 
me in the same field ; and it may perhaps be as well 
that I should hold them back, till the experience of a 
northern winter or two shall have enabled me to test 
the conclusions which they point to. For the present 
I content myself with a mere resume. My immedi- 
ate subject is the growth of the pack. 
On the twelfth of September, while attempting 
with a free top-gall-ant breeze to make our way to the 
east, the thermometer indicating a mean daily tem- 
perature of +14° or 18° below the freezing point, the 
sea was observed to gradually thicken around us. A 
pasty sludge, formed of crystals broken up by the ac- 
tion of the waves, began to resolve itself into those 
polyhedral plates described by Scoresby under the 
name of pancake ice. 
SLCDGS. PANCAKB. 
As the wind increased, these were rolled into act- 
ual spheroids; their forces being regulated by the 
laws which control equally compressed spheres, giv- 
