Kerry drew the curtain back, and threw open the folding leaves of the window.  He found himself looking out upon the leads of Albemarle Street.  No stars and no moon showed through the grey clouds draping the wintry sky, but a dim and ghostly half-light nevertheless rendered the ugly expanse visible from where he stood.

On one side loomed a huge tank, to the brink of which a rickety wooden ladder invited the explorer to ascend.  Beyond it were a series of iron gangways and ladders forming part of the fire emergency arrangements of the neighboring institution.  Straight ahead a section of building jutted up and revealed two small windows, which seemed to regard him like watching eyes.

He walked out on to the roof, looking all about him.  Beyond the tank opened a frowning gully—­the Arcade connecting Albemarle Street with old Bond Street; on the other hand, the scheme of fire gangways was continued.  He began to cross the leads, going in the direction of Bond Street.  Coombes watched him from the study.  When he came to the more northerly of the two windows which had attracted his attention, he knelt down and flashed the ray of his torch through the glass.

A kind of small warehouse was revealed, containing stacks of packages.  Immediately inside the window was a rough wooden table, and on this table lay a number of smaller packages, apparently containing cigarettes.

Kerry turned his attention to the fastening of the window.  A glance showed him that it was unlocked.  Resting the torch on the leads, he grasped the sash and gently raised the window, noting that it opened almost noiselessly.  Then, taking up the torch again, he stooped and stepped in on to the table below.

It moved slightly beneath his weight.  One of the legs was shorter than its fellows.  But he reached the floor as quietly as possible, and instantly snapped off the light of the torch.

A heavy step sounded from outside—­someone was mounting the stairs—­ and a disk of light suddenly appeared upon the ground-glass panel of the door.

Kerry stood quite still, chewing steadily.

“Who’s there?” came the voice of the constable posted on Kazmah’s landing.

The inspector made no reply.

“Is there anyone here?” cried the man.

The disk of light disappeared, and the alert constable could be heard moving along the corridor to inspect the other offices.  But the ray had shone upon the frosted glass long enough to enable Kerry to read the words painted there in square black letters.  They had appeared reversed, of course, and had read thus: 

.OC ETTERAGIC SINABUC

CHAPTER XI

THE DRUG SYNDICATE

At six-thirty that morning Margaret Halley was aroused by her maid—­ the latter but half awake—­and sitting up in bed and switching on the lamp, she looked at the card which the servant had brought to her, and read the following: