Three Girls from School by L.T. Meade

No one would have supposed that Annie Brooke, brought up so carefully by such an uncle as the Rev Maurice Brooke, would so easily yield to one temptation after another. But it is one of the most surprising and true things in life that it is the first wrong-doing that counts. It is over the first wrong action that we struggle and hesitate. We shrink away then from the edge of the abyss, and if we do yield to temptation our consciences speak loudly.

But conscience is of so delicate a fibre, so sensitive an organisation, that if she is neglected her voice grows feeble. She ceases to reproach when reproach is useless, and so each fall, be it great or little, is felt less than the last.