But directly underneath the steep
escarpment of rock on the far side of the pool it lay foamless and
black, a still backwater of great depth. Above the altar-like erection
again the ground rose up seven rough-hewn steps to the gate itself, on
each side of which, to the height of about four feet, ran the circular
wall of the castle. Inside again were the remains of partition walls
between the three chambers, and it was in the one nearest to the river
gate that we determined to conceal ourselves that night. From there,
should the witch and Sandy keep tryst at the altar, any sound of
movement would reach us, and through the aperture of the gate itself we
could see, concealed in the shadow of the wall, whatever took place at
the altar or down below at the pool. The lodge, finally, was but a short
ten minutes away, if one went in the direct line, so that by starting at
a quarter to twelve that night, we could enter the Picts’ Castle by the
gate away from the river, thus not betraying our presence to those who
might be waiting for the moment when the moon should shine through the
lancet window in the wall of rock on to the altar in front of the river
gate. Night fell very still and windless, and when not long before midnight we
let ourselves silently out of the lodge, though to the east the sky was
clear, a black continent of cloud was creeping up from the west, and had
now nearly reached the zenith. Out of the remote fringes of it
occasional lightning winked, and the growl of very distant thunder
sounded drowsily at long intervals after. But it seemed to me as if
another storm hung over our heads, ready every moment to burst, for the
oppression in the air was of a far heavier quality than so distant a
disturbance could have accounted for. To the east, however, the sky was
still luminously clear; the curiously hard edges of the western cloud
were star-embroidered, and by the dove-coloured light in the east it was
evident that the moonrise over the moor was imminent. And though I did
not in my heart believe that our expedition would end in anything but
yawns, I was conscious of an extreme tension and rawness of nerves,
which I set down to the thunder-charged air. For noiselessness of footstep we had both put on india-rubber soled
shoes, and all the way down to the pool we heard nothing but the distant
thunder and our own padded tread. Very silently and cautiously we
ascended the steps of the gate away from the river, and keeping close to
the wall inside, sidled round to the river gate and peered out. For the
first moment I could see nothing, so black lay the shadow of the
rock-wall opposite across the pool, but by degrees I made out the lumps
and line of the glimmering foam which streaked the water. High as the
river was running this morning it was infinitely more voluminous and
turbulent now, and the sound of it filled and bewildered the ear with
its sonorous roaring. Only under the very base of the rock opposite it
ran quite black and unflecked by foam: there lay the deep still surface
of the backwater. Then suddenly I saw something black move in the
dimness in front of me, and against the grey foam rose up first the
head, then the shoulders, and finally the whole figure of a woman
coming towards us up the bank. Behind her walked another, a man, and the
two came to where the altar of stone had been newly erected and stood
there side by side silhouetted against the churned white of the stream. Hugh had seen too, and touched me on the arm to call my attention. So
far then he was right: there was no mistaking the stalwart proportions
of Sandy. Suddenly across the gloom shot a tiny spear of light, and momentarily as
we watched, it grew larger and longer, till a tall beam, as from some
window cut in the rock opposite, was shed on the bank below us. It moved
slowly, imperceptibly to the left till it struck full between the two
black figures standing there, and shone with a curious bluish gleam on
the flat stone in front of them. Then the roar of the river was suddenly
overscored by a dreadful screaming voice, the voice of a woman, and from
her side her arms shot up and out as if in invocation of some power. At
first I could catch none of the words, but soon from repetition they
began to convey an intelligible message to my brain, and I was listening
as in the paralytic horror of nightmare to a bellowing of the most
hideous and un-nameable profanity. What I heard I cannot bring myself to
record; suffice it to say that Satan was invoked by every adoring and
reverent name, that cursing and unspeakable malediction was poured forth
on Him whom we hold most holy. Then the yelling voice ceased as
suddenly as it had begun, and for a moment there was silence again, but
for the reverberating river. Then once more that horror of sound was uplifted. “So, Catrine Gordon,” it cried, “I bid ye in the name of my master and
your’s to rise from where ye lie. Up with ye--up!”

Once more there was silence; then I heard Hugh at my elbow draw a quick
sobbing breath, and his finger pointed unsteadily to the dead black
water below the rock. And I too looked and saw. Right under the rock there appeared a pale subaqueous light, which waved
and quivered in the stream. At first it was very small and dim, but as
we looked it seemed to swim upwards from remote depths and grew larger
till I suppose the space of some square yard was illuminated by it. Then
the surface of the water was broken, and a head, the head of a girl,
dead-white and with long, flowing hair, appeared above the stream. Her
eyes were shut, the corners of her mouth drooped as in sleep, and the
moving water stood in a frill round her neck. Higher and higher rose the
figure out of the tide, till at last it stood, luminous in itself, so it
appeared, up to the middle. The head was bent down over the breast, and
the hands clasped together. As it emerged from the water it seemed to
get nearer, and was by now half-way across the pool, moving quietly and
steadily against the great flood of the hurrying river. Then I heard a man’s voice crying out in a sort of strangled agony. “Catrine!” it cried; “Catrine! In God’s name; in God’s name!”

In two strides Sandy had rushed down the steep bank, and hurled himself
out into that mad swirl of waters. For one moment I saw his arms flung
up into the sky, the next he had altogether gone. And on the utterance
of that name the unholy vision had vanished too, while simultaneously
there burst in front of us a light so blinding, followed by a crack of
thunder so appalling to the senses, that I know I just hid my face in my
hands. At once, as if the flood-gates of the sky had been opened, the
deluge was on us, not like rain, but like one sheet of solid water, so
that we cowered under it.