“This stretch of passage,” came another roar from Sir Lionel, “dates back to Roman days or even earlier!  By God!  It’s almost incredible!”

And now Smith and Kennedy, who lid, were up to their knees in a running tide.  An icy shower-bath drenched us from above; ahead was a solid wall of falling water.  Again, and louder, nearer, boomed and rattled the thunder; its mighty voice was almost lost in the roar of that subterranean cataract.  Nayland Smith, using his hands as a megaphone, cried;—­

“Failing the evidence that others have passed this way, I should not dare to risk it!  But the river is less than forty feet wide at the point below Monkswell; a dozen paces should see us through the worst!”

I attempted no reply.  I will frankly admit that the prospect appalled me.  But, bracing himself up as one does preparatory to a high dive, Smith, nodding to Kennedy to proceed, plunged into the cataract ahead....

CHAPTER XL

THE BLACK CHAPEL

Of how we achieved that twelve or fifteen yards below the rocky bed of the stream the Powers that lent us strength and fortitude alone hold record.  Gasping for breath, drenched, almost reconciled to the end which I thought was come—­I found myself standing at the foot of a steep flight of stairs roughly hewn in the living rock.

Beside me, the extinguished lamp still grasped in his hand, leant Kennedy, panting wildly and clutching at the uneven wall.  Sir Lionel Barton had sunk exhausted upon the bottom step, and Nayland Smith was standing near him, looking up the stairs.  From an arched doorway at their head light streamed forth!

Immediately behind me, in the dark place where the waters roared, opened a fissure in the rock, and into it poured the miniature cataract; I understood now the phenomenon of minor whirlpools for which the little river above was famous.  Such were my impressions of that brief breathing-space; then—­

“Have your pistols ready!” cried Smith.  “Leave the lamp, Kennedy.  It can serve us no further.”

Mustering all the reserve that remained to us, we went, pell-mell, a wild, bedraggled company, up that ancient stair and poured into the room above....

One glance showed us that this was indeed the chapel of Asmodeus, the shrine of Satan where the Black Mass had been sung in the Middle Ages.  The stone altar remained, together with certain Latin inscriptions cut in the wall.  Fu-Manchu’s last home in England had been within a temple of his only Master.

Save for nondescript litter, evidencing a hasty departure of the occupants, and a ship’s lantern burning upon the altar, the chapel was unfurnished.  Nothing menaced us, but the thunder hollowly crashed far above.  To cover his retreat, Fu-Manchu had relied upon the noxious host in the passage and upon the wall of water.  Silent, motionless, we four stood looking down at that which lay upon the floor of the unholy place.