Suddenly he felt an insurmountable desire to look at Nell, and directed his steps towards the tree.
"In Desert and Wilderness"
Henryk Sienkiewicz
Still, if the young lady liked him, singular as the choice might appear, other objections need not be insurmountable.
"The Martins Of Cro' Martin, Vol. II (of II)"
Charles James Lever
A pitiful band of the deaf, fighting insurmountable odds to win back the human dignity of half the galaxy!
"The Instant of Now"
Irving E. Cox, Jr.