But could she? Difficulties came crowding thick and fast into her thoughts. It was going to snow; the soft broad flakes were falling already. Could she row the two miles to the Big Dipper in the darkness and the snow? If she could, dare she leave Nellie all alone in the house? Oh, she couldn't! Somebody at the Harbour Head would surely notice that the Big Dipper light was unlighted and would go over to investigate the cause. But suppose they shouldn't? If the snow came thicker they might never notice the absence of the light. And suppose there was a ship away out there, as there nearly always was, with the dangerous rocks and shoals of the outer harbour to pass, with precious lives on board and no guiding beacon on the Big Dipper. Mary Margaret hesitated no longer. She must go. Bravely, briskly and thoughtfully she made her preparations. First, the fire was banked and the draughts dosed; then she wrote a little note for her mother and laid it on the table. Finally she wakened Nellie. "Nellie," said Mary Margaret, speaking very kindly and determinedly, "there is no light on the Big Dipper and I've got to row over and see about it. I'll be back as quickly as I can, and Mother and Uncle Martin will soon be here. You won't be afraid to stay alone, will you, dearie? You mustn't be afraid, because I have to go. And, Nellie, I'm going to tie you in your chair; it's necessary, because I can't lock the door, so you mustn't cry; nothing will hurt you, and I want you to be a brave little girl and help sister all you can." Nellie, too sleepy and dazed to understand very clearly what Mary Margaret was about, submitted to be wrapped up in quilts and bound securely in her chair. Then Mary Margaret tied the chair fast to the wall so that Nellie couldn't upset it. That's safe, she thought. Nellie can't run out now or fall on the stove or set herself afire. Mary Margaret put on her jacket, hood and mittens, and took Uncle Martin's lantern. As she went out and closed the door, a little wail from Nellie sounded on her ear. For a moment she hesitated, then the blackness of the Big Dipper confirmed her resolution. She must go. Nellie was really quite safe and comfortable. It would not hurt her to cry a little, and it might hurt somebody a great deal if the Big Dipper light failed. Setting her lips firmly, Mary Margaret ran down to the shore. Like all the Harbour girls, Mary Margaret could row a boat from the time she was nine years old. Nevertheless, her heart almost failed her as she got into the little dory and rowed out. The snow was getting thick. Could she pull across those black two miles between the Dippers before it got so much thicker that she would lose her way? Well, she must risk it. She had set the light in the kitchen window; she must keep it fair behind her and then she would land on the lighthouse beach. With a murmured prayer for help and guidance she pulled staunchly away.