watchful with anxious thoughts
Walton is anxious not just because his way is barred but because the
icefield, in expanding, could easily crush the hull of his ship. That
process, called "nipping," was a major danger to wooden-hulled boats in
From Elisha Kent Kane, The United States Grinnell Expedition in Search
of Sir John Franklin (Philadelphia: Childs and Peterson, 1857),
facing p. 120.
From Elisha Kent Kane, Arctic Explorations in the Years 1853, '54,
'55 (Philadelphia: Childs and Peterson, 1856), facing p. 144.