‘’Pity you haven’t a little—­occasionally.’

’I have believed a certain type of patient in my time.  It’s always the same.  For reasons not given in the consulting-room they take to the drug.  Certain symptoms follow.  They will swear to you, and believe it, that they took the drug to mask the symptoms.  What does your man use?  Najdolene?  I thought so.  I had practically the duplicate of your case last Thursday.  Same old Najdolene—­same old lie.’

‘Tell me the symptoms, and I’ll draw my own inferences, Johnnie.’

’Symptoms!  The girl was rank poisoned with Najdolene.  Ramping, stamping possession.  Gad, I thought she’d have the chandelier down.’

‘Mine came unstuck too, and he has the physique of a bull,’ said Gilbert.  ‘What delusions had yours?’

’Faces—­faces with mildew on them.  In any other walk of life we’d call it the Horrors.  She told me, of course, she took the drugs to mask the faces. Post hoc, propter hoc again.  All liars!’

‘What’s that?’ said the senior K.C. quickly.  ‘Sounds professional.’

‘Go away!  Not for you, Sandy.’  Sir John turned a shoulder against him and walked with Gilbert in the chill evening.

To Conroy in his chambers came, one week later, this letter: 

DEAR MR. CONROY—­If your plan of a night’s trip on the 17th still holds good, and you have no particular destination in view, you could do me a kindness.  A Miss Henschil, in whom I am interested, goes down to the West by the 10.8 from Waterloo (Number 3 platform) on that night.  She is not exactly an invalid, but, like so many of us, a little shaken in her nerves.  Her maid, of course, accompanies her, but if I knew you were in the same train it would be an additional source of strength.  Will you please write and let me know whether the 10.8 from Waterloo, Number 3 platform, on the 17th, suits you, and I will meet you there?  Don’t forget my caution, and keep up the tonic.—­Yours sincerely,

     L. RUTHERFORD GILBERT.

‘He knows I’m scarcely fit to look after myself,’ was Conroy’s thought.  ‘And he wants me to look after a woman!’

Yet, at the end of half an hour’s irresolution, he accepted.

Now Conroy’s trouble, which had lasted for years, was this: 

On a certain night, while he lay between sleep and wake, he would be overtaken by a long shuddering sigh, which he learned to know was the sign that his brain had once more conceived its horror, and in time—­in due time—­would bring it forth.

Drugs could so well veil that horror that it shuffled along no worse than as a freezing dream in a procession of disorderly dreams; but over the return of the event drugs had no control.  Once that sigh had passed his lips the thing was inevitable, and through the days granted before its rebirth he walked in torment.  For the first two years he had striven to fend it off by distractions, but neither exercise nor drink availed.  Then he had come to the tabloids of the excellent M. Najdol.  These guarantee, on the label, ’Refreshing and absolutely natural sleep to the soul-weary.’  They are carried in a case with a spring which presses one scented tabloid to the end of the tube, whence it can be lipped off in stroking the moustache or adjusting the veil.