In fine, I was so far from being persuaded that Smith had expected company, that I gravely suspected that he had made quite other arrangements; arrangements of the most perfidious character. And as the horses' hoofs rang monotonously on the hard road, and we rose and fell in the saddle, and I peered forward into the gloom, fearing all things and doubting all things, for certain I feared and doubted nothing so much as I did the dark and secret man beside me; whose scheming brain, spinning plot within plot, each darker and more involved than the other, kept all my ingenuity at a stretch to overtake the final end and purpose he had at heart. Indeed, I despair of conveying to others how gravely this sombre companionship and more sombre uncertainty aggravated the terrors of a journey, that at the best of times must have been little to my taste. To the common risks of the road, deserted at that hour by all save cutpurses and rogues, was added a suspicion, as much more harassing than these, as unseen dangers ever surpass the known. It was in vain that I strove to divert my mind from the figure by my side; neither the bleak heath above Greenwich--whence we looked back at the reddish haze that canopied London, and forward to where the Thames marshes stretched eastward under night--nor the gibbet on Dartford Brent, where a body hung in chains, poisoning the air, nor the light that shone dim and solitary, far to the left, across the river, and puzzled me until he told me that it was Tilbury--neither of these things, I say, though they occupied my thoughts by turns and for a moment, had power to drive him from my mind, or divert my fears to dangers more apparent. And in this mood, now glancing askance at him, and now moving uneasily under his gaze, I might have ridden to Rochester if my ear had not caught--I think when we were two or three miles short of the city--the sound of a horse trotting fast on the road behind us. At first it followed so faintly on the breeze that I doubted, thinking it might be either the echo of our hoofs, or a pulse beating in my ears. Then, on a hard piece of ground, it declared itself unmistakably; and again as suddenly it died away. At that I spoke involuntarily. "He has stopped," I said. Smith laughed in his teeth. "He is crossing the wet bottom, fool--by the creek," he said. And before I could answer him the dull sound of a horse galloping fast, but moving on the turf that ran alongside the road, proved him to be right. "Draw up!" he whispered in something of a hurry, and then, as I hesitated, "Do you hear?" he continued, sharply seizing my rein. "What do you fear? Do you think that night birds prey on night birds?"