Three persons,—­two sisters and their brother, who was younger than themselves, members of a decent English family, were going on a trip round the world.  They were young, adventurous, and—­not to put too fine a point on it—­foolhardy.  The evening after their arrival in Cairo, by way of what is called ‘a lark,’ in spite of the protestations of people who were better informed than themselves, they insisted on going, alone, for a ramble through the native quarter.

They went,—­but they never returned.  Or, rather the two girls never returned.  After an interval the young man was found again,—­ what was left of him.  A fuss was made when there were no signs of their re-appearance, but as there were no relations, nor even friends of theirs, but only casual acquaintances on board the ship by which they had travelled, perhaps not so great a fuss as might have been was made.  Anyhow, nothing was discovered.  Their widowed mother, alone in England, wondering bow it was that beyond the receipt of a brief wire, acquainting her with their arrival at Cairo, she had heard nothing further of their wanderings, placed herself in communication with the diplomatic people over there,—­ to learn that, to all appearances, her three children had vanished from off the face of the earth.

Then a fuss was made,—­with a vengeance.  So far as one can judge the whole town and neighbourhood was turned pretty well upside down.  But nothing came of it,—­so far as any results were concerned, the authorities might just as well have left the mystery of their vanishment alone.  It continued where it was in spite of them.

However, some three months afterwards a youth was brought to the British Embassy by a party of friendly Arabs who asserted that they had found him naked and nearly dying in some remote spot in the Wady Haifa desert.  It was the brother of the two lost girls.  He was as nearly dying as he very well could be without being actually dead when they brought him to the Embassy,—­and in a state of indescribable mutilation.  He seemed to rally for a time under careful treatment, but he never again uttered a coherent word.  It was only from his delirious ravings that any idea was formed of what had really occurred.

Shorthand notes were taken of some of the utterances of his delirium.  Afterwards they were submitted to me.  I remembered the substance of them quite well, and when Mr Lessingham began to tell me of his own hideous experiences they came back to me more clearly still.  Had I laid those notes before him I have little doubt but that he would have immediately perceived that seventeen years after the adventure which had left such an indelible scar upon his own life, this youth—­he was little more than a boy—­had seen the things which he had seen, and suffered the nameless agonies and degradations which he had suffered.  The young man was perpetually raving about some indescribable den of horror which was own brother to Lessingham’s temple and about