c. 1400. Found. St. Bartholomew’s (1923), 17. As yt were with an vnpenytrable scochyn wardid and defendyd.
1581. J. Bell, Haddon’s Answ. Osor., 187 b. God accordyng to his unpenetrable counsell doth determine all thinges.
1630. J. Taylor (Water P.), Pennilesse Pilgr., Wks. I. 129/2. The Foundation and Walls are vnpenetrable, the Rampiers impregnable.
1652. G. Herbert, Priest to the Temple, xxxiv. 152. To them an unpenetrable rock, an unaccessible desert.
