Harriet walked sturdily onwards, the light pack upon her shoulders interfering little with her progress. She was twenty-eight years old, dark, slight, with a skin naturally a little sallow, but now tanned to an agreeable biscuit-colour by sun and wind. Persons of this fortunate complexion are not troubled by midges and sunburn, and Harriet, though not too old to care for her personal appearance, was old enough to prefer convenience to outward display. Consequently, her luggage was not burdened by skin-creams, insect-lotion, silk frocks, portable electric irons or other impedimenta beloved of the ‘Hikers’ Column’. She was dressed sensibly in a short skirt and thin sweater and carried, in addition to a change of linen and an extra provision of footwear, little else beyond a pocket edition of Tristram Shandy, a vest-pocket camera, a small first-aid outfit and a sandwich lunch.
It was about a quarter to one when the matter of the lunch began to loom up importantly in Harriet’s mind. She had come about eight miles on her way to Wilvercombe, having taken things easily and made a detour to inspect certain Roman remains declared by the guide-book to be ‘of considerable interest’. She began to feel both weary and hungry, and looked about her for a suitable lunching-place.
The tide was nearly out now, and the wet beach shimmered golden and silvery in the lazy noonlight. It would be pleasant, she thought, to go down, to the shore — possibly even to bathe, though she did not feel too certain about that, having a wholesome dread of unknown shores and eccentric currents. Still, there was no harm in going to see. She stepped over the low wall which bounded the road on the seaward side and set about looking for a way down. A short scramble among the rocks tufted with scabious and sea-pink brought her easily down to the beach. She found herself in a small cove, comfortably screened from the wind by an outstanding mass of cliff, and with a few convenient boulders against which to sit. She selected the cosiest spot, drew out her lunch and Tristram Shandy, and settled down.
There is no more powerful lure to slumber than hot sunshine on a sea-beach after lunch; nor is the pace of Tristram Shandy so swift as to keep the faculties working at high pressure. Harriet found the book escaping from her fingers.
Twice she caught it back with a jerk; the third time it eluded her altogether. Her head drooped over an an unbecoming angle. She dozed off.
She was awakened suddenly by what seemed to be a shout or cry almost in her ear. As she sat up, blinking, a gull swooped close over her head, squawking and hovering over a stray fragment of sandwich. She shook herself reprovingly and glanced at her wrist-watch. It was two o’clock. Realising with satisfaction that she could not have slept very long, she scrambled to ‘her feet, and shook the crumbs from her lap. Even now, she did not feel very energetic, and there was plenty of time to make Wilvercombe before evening. She glanced out to sea, where a long belt of shingle and a narrow strip of virgin and shining sand stretched down to the edge of the water.
There is something about virgin sand which arouses all the worst instincts of the detective-story writer. One feels an irresistible impulse to go and make footprints all over it. The excuse which the professional mind makes to itself is that the sand affords a grand opportunity for observation and experiment. Harriet was no stranger to this impulse. She determined to walk out across that tempting strip of sand. She gathered her various belongings together and started off across the loose shingle observing, as she had often observed before, that footsteps left no distinguishable traces in the sand region above high-water mark.
Soon, a little belt of broken shells and half-dry seaweed showed that the tide-mark had been reached.
‘I wonder,’ said Harriet to herself, ‘whether I ought to be able to deduce something or other about the state of the tides. Let me see. When the tide is at neaps, it doesn’t rise or fall so far as when it is at springs. Therefore, if that is the case, there ought to be two seaweedy marks — one quite dry and farther in, showing the highest point of spring tides, and one damper and farther down, showing today’s best effort.’ She glanced backwards and forwards. ‘No; this is the only tide-mark. I deduce, therefore, that I have arrived somewhere about the top of springs, if that’s the proper phrase. Perfectly simple, my dear Watson. Below tide-mark, I begin to make definite footprints. There are no others anywhere, so that I must be the only person who has patronised this beach since last high tide, which would be about — ah! yes, there’s the difficulty. I know, there should be about twelve hours between one high tide and the next, but I haven’t the foggiest notion whether the, sea is coming in or going out. Still, I do know it was going out most of the time as I came along, and it looks a long way off now. If I say that nobody has been here for the last five hours, I shan’t be far out. I’m making very pretty footprints now, and the sand is, naturally, getting wetter. I’ll see how it looks when, I run.’
She capered a few paces accordingly, noticing the greater depth of the toe-prints and the little spurt of sand thrown out at each step. This outburst of energy brought her round the point of the cliff and into a much larger bay, the only striking feature of which was a good-sized rock, standing down at the sea’s edge, on the other side of the point. It was roughly triangular in shape, standing about ten feet out of the water, and seemed to be crowned with a curious lump of black seaweed.
A solitary rock is always attractive. All right-minded people feel an overwhelming desire to scale and sit upon it. Harriet made for it without any mental argument, trying to draw a few deductions as she went.
‘Is that rock covered at high tide? Yes, of course, or it wouldn’t have seaweed on top. Besides, the slope of the shore proves it. I wish I was better at distances and angles, but I should say it would be covered pretty deep. How odd that it should have seaweed only in that lump at the top. You’d expect it to be at the foot, but the sides seem quite bare, nearly down to the water. I suppose it is seaweed. It’s very peculiar. It looks almost more like a man lying down; is it possible for seaweed to be so very — well, so very localised?’
She gazed at the rock with a faint stirring of curiosity, and went on talking aloud to herself, as was her rather irritating habit.
‘I’m dashed if it isn’t a man lying down. What a silly place to choose. He must feel like a bannock on a hot girdle. I could understand it if he was a sun-bathing fan, but he seems to have. got all his clothes on. A dark suit at that. He’s very quiet. He’s probably fallen asleep. If the tide comes in at all fast, he’ll be cut off, like the people in the silly magazine stories. Well, I’m not going to rescue him. He’ll have to take his socks off and paddle, that’s all. There’s plenty of time yet.’