that day she learned to hold herself from slipping by wedging a shoulder between two small rocky outcroppings and then to free herself upward by arching her back and turning sideways , this way , then that , slowly and gently and no weight whatsoever on those slip-slidey canvas shoes , until she could carefully reach an arm upward through the hole and be pulled up by the big burly hand attached to the soft , patient voice that had guided her .