p it. . . . Sodom and Gomorrah
. . . basaltic, I've heard . . . we'd better run!'

"'What the devil have you done?' I asked, close to his ear.

"'Opened that stink-pot,' Farrell answered, taking two steps at a
time. He gained the pavement and paused, turning on me.

"'Lucky they can't afford to keep a commissionaire.--How long do
these things take, as a rule, before going off?'

"'What things?' I asked.

"'Maroons, don't you call 'em?' said he, feeling in a foolish sort of
way at his breast-pocket, as if for his pince-nez. 'I got the
slow-match going with the end of my cigar, careless-like. How long
do they take as a rule?'

"Well, a handsome detonation below-stairs answered him upon that
instant.

"Farrell clutched my arm, and we ran."

NIGHT THE SIXTH.

THE ADVENTURE OF THE PICTUREDROME.

"Farrell could sprint," continued Jimmy. "You may have noticed that
a lot of these round-bellied men have quite a good turn of speed for
a short course. In spite of his fur coat he led by a yard or two:
but this was partly because I hung back a little, on the chance of
having to fight a rear-guard action.

"I could hear no shouts or footsteps in our wake, and this struck me
as strange at the time. On second thoughts, however, I dare say the
management and frequenters of the 'Catalafina' have more than a
bowing acquaintance with infernal machines. A daisy by the river's
brim . . . to them a simple maroon would be nothing to write home
about, nor the sort of incident to justify telephoning for an
inquisitive police. By the mercy of Heaven, too, we encountered no
member of the Force in our flight. I suppose that constables are
rare in Soho.

"Farrell led for a couple of blocks as an American writer would put
it; dived down a side street to the right; sped like an arrow for a
couple of hundred yards; then darted around another turning, again to
the right. I put on a spurt and caught him by his fur collar.
'Look here,' I said, 'I don't hear anyone in chase. We are the
wicked fleeing, whom no man pursueth. I don't quite understand why.
Maybe sulphuretted hydrogen's their favourite perfume. They don't
use it in their bath, because . . . well, never mind. What I have to
talk at this moment is mathematics. I don't know how you reason it
out; but to me it's demonstrable that if we keep turning to the right
like this we shall find ourselves back at the door of your infernal
'Catalafina.' Inevitably,' I sa