So early, in truth, that in the days when tropical nature was to be found, where now lie eternal unthawing snows, one could cross almost by dry land from Norway via Iceland and Greenland, to the lands that at present surround Hudson's Bay.
Source: wiktionary
What fairer home than Earth's eternal hill
Paved with unthawing snow, lit with the sun's
Unwinking lamp, […]
Source: wiktionary
Although the women found the picture of Jack in spike heels irresistible, their own feet, half frozen, thawing and unthawing, stung with such fierce poignancy that their humor was invaded by sympathy, and nobody laughed. "Here I was, broke," Marlis went on. "Knocked up. Which I did not expect, but which I halfway treasured and half resented […]"
Source: wiktionary