midnight
From the recesses of their memories the girls raked up every superstition of which they had ever heard . These had to be divided into the possible and the impossible . There are limits of liberty in a girls ' school , and it was manifestly infeasible , as well as very chilly , to attempt to stray out alone at the stroke of twelve , robed merely in a nightgown , and fetch three pails of water to place by one 's bedside . Gowan 's north country recipe for divination was equally impracticable -- to go out at midnight , and `` dip your smock in a south-running spring where the lairds ' lands meet , '' then hang it to dry before the fire . They discussed it quite seriously , however , in all its various aspects . `` To begin with , what exactly is a smock ? '' asked Carmel .