Snake and sword

Even as she stood poised, one foot on the ground, the other on the stool, both hands gripping the high shelf, she felt the reptile whipping, writhing, jerking, lashing, flogging at her ankle and instep, coiling round her leg.... And in the fraction of a second the thought flashed through her mind: "If its head is under my foot, or too close to my foot for its fangs to reach me, I am safe while I remain as I am. If its head is free I am doomed-and matters cannot be any the worse for my keeping as I am."