“That may prove considerably more difficult,” I observed. “Rumours are such nebulous, elusive things. It is almost impossible to get a firm grasp upon them; and that which cannot be firmly grasped cannot easily be cast down and beaten. You have also, it seems to me, the difficult problem of trying to prove a negative, that is, that Reid had no close connection with the dead girl, and I cannot see how you can possibly prove such a general notion, especially now that three years have passed since the time in question.”

“You undoubtedly state the matter fairly,” returned Holmes after a moment. “But to have explained the nature of Captain Reid’s troubles leaves our commission but half finished, Watson. We must do all we can to disprove these foul accusations which are laid against him. If we fail, then we fail, but at least we shall know that we have done all that we could. After all, what is the alternative? That Captain Reid leave his house and home for ever? For it would surely be intolerable to him to remain here in the present circumstances. But if he leaves his home now, he leaves it with this foul stain still upon his character. That alternative is surely unthinkable. Besides, bad as his situation is, it could yet become worse. So far, the rumours that besmirch his name are confined to this parish alone. But rumours, as you know, are like rank weeds and apt to spread wherever they can. It is possible that unless we destroy this particular specimen root and branch, it will spread further afield, perhaps to the West Sussex Regiment, or even as far as London Society.”

“What you say is true,” I concurred, “but I fear the case is quite hopeless, Holmes. There seems to me no way in which Reid’s innocence can be proved.”

“It may be that the only way to prove our client’s innocence is to prove the guilt of another,” responded my friend after a moment in a considered tone. “Now, as you will appreciate, Watson, I have no desire to expose the moral lapses of another man to public view, but if it is the only way to clear the name of an innocent man, then I believe I have no choice in the matter. Besides, it must be remembered that this man, whoever he is, has been content to allow our client to suffer quite unmerited condemnation for the past three years.”

“But what can you possibly hope to discover after so much time has elapsed?” I protested. “What conceivable evidence could remain?”

“Let us not prejudge the matter,” returned my friend with a shake of the head. “We shall proceed in an orderly, scientific manner and see what we turn up. Tomorrow morning I intend to look over the pond where the girl was drowned. Mr Yarrow has very kindly agreed to meet me there at two o’clock, to act as my guide and to furnish me with a few more details of the matter. He is taking lunch with Captain Reid’s father at Oakbrook Hall tomorrow, as he has an appointment to see him about some business concerning the church roof, and he will come directly to the pool from there. Let us hope that this fine weather continues for a little longer, and then we shall see if we cannot make some further progress!”

III: THE WILLOW POOL

The following day dawned bright and clear. My bedroom at the White Hart overlooked a garden at the rear, and as I dressed I could see from the bedraggled state of the vegetation there that it had rained during the night. Already, however, the bright sunshine was warming the ground and raising a thin haze among the trees, and it showed every promise of a fine day ahead.

When I descended to the dining room, I was informed that Holmes had risen early and had already gone out. He returned as I awaited breakfast with a large-scale map of the district, which he had purchased at the local post office.

“The village high street appears to lie on the line of a Roman road,” said he, spreading out his map in front of him. “See how it runs in a perfectly straight line from south to north. The White Hart stands here in the market place, at the south end of the high street,” he continued, indicating the place on the map. “At the north end, as you see, just above the crossroads, stands the church. There the road takes a sweeping curve to the west round the churchyard, before resuming its course due north again. A mile or so further on, on the west side of the road, lies the entrance to the Oakbrook estate. A little way beyond that, the road crosses a small stream. On the west side of the road at that point is a small spinney, marked as Jenkin’s Clump. The stretch of water indicated within it must therefore be the Willow Pool. Another half a mile or so further north up the road lies the entrance to Topley Grange. The sky promises fair weather, Watson, and I have arranged with Mr Coleman, our landlord, to furnish us with a flask of ginger beer and a little bread and cheese for our lunch, so when you are ready, our expedition can begin!”

The sun was warm on our backs as we made our way up the village street and past the long, curving wall of the churchyard. To the side of the church stood the vicarage. Beyond that, open farmland stretched as far as the eye could see, and the road dipped slightly, then began a long, gentle climb to the higher, rolling country to the north. On either side of the road, the hedgerows were ablaze with colour, the foliage a vivid mixture of greens, yellows and reds, among which shone the bright red berries of the hawthorn and the stout hips of the wild roses. Off to our right, where a ploughing team was at work in a field, flocks of lapwings and rooks circled noisily overhead, and all about us the air was full of the rich, mature scents of autumn.

We had been following this pleasant road for about ten minutes when the hedge on our left gave way to a high brick wall. A little way along this was a wide gateway, flanked with old, lichen-blotched stone pillars. A sign on one of these indicated that this was the entrance to Oakbrook Hall, and through the gateway I could see a long shaded avenue of oaks and elms, curving away to the left. A little further on, the wall gave way once more to a hawthorn hedge, punctuated at intervals by spreading oak trees, and the road dropped into a small vale. At the bottom of the vale was a stone bridge, spanning a stream. As we approached this, a gentleman on horseback came trotting down the road towards us, on the far side of the stream. He crossed the bridge, then slowed his horse to a walk as he approached us. He was, I observed, a young man of perhaps five-and-twenty, and he was dressed in a very smart riding costume.

“The remains of the Roman villa are the other way,” he called out in a peremptory fashion.

“I am obliged to you,” returned Holmes in an affable tone, “but we are not looking for the villa.”

“You’ll not find anything up this way,” persisted the other, drawing his horse to a halt.

“Well, we shall find that footpath, at least,” said Holmes, pointing to a gap in the vegetation a little way ahead of us, just before the bridge, which indicated the entrance to the path up to the Willow Pool.

“What on earth do you want to go up there for?” exclaimed the young man in a tone of surprise and disdain. “There’s nothing of interest up there.”

“Well, well. No doubt the exercise will be beneficial, anyhow!”

The young man snorted. “You’re down here from London, aren’t you?” he continued after a moment.

“That is so. And you, if I might venture to speculate, are a resident of these parts.”

The young man did not reply, but flicked his horse forward. “Please yourself,” he called over his shoulder in an unpleasant tone, “but you’re wasting your time.”

“We shall see about that,” said Holmes to me as we resumed our walk. “It may be, Watson,” he added, “that that egregiously rude young man is Admiral Blythe-Headley’s son, Anthony, to whom Reid referred the other day.”