d! it nearly choked me!"

Dr. Cairn nodded grimly.

"It is all over the house," he continued, "in every room that I have
entered. They are used to it, and evidently do not notice it, but
coming in from the clean air, it is--"

"Abominable, unclean--unholy!"

"We know it," continued Dr. Cairn softly--"that smell of unholiness;
we have good reason to know it. It heralded the death of Sir Michael
Ferrara. It heralded the death of--another."

"With a just God in heaven, can such things be?"

"It is the secret incense of Ancient Egypt," whispered Dr. Cairn,
glancing towards the open door; "it is the odour of that Black Magic
which, by all natural law, should be buried and lost for ever in the
tombs of the ancient wizards. Only two living men within my knowledge
know the use and the hidden meaning of that perfume; only one living
man has ever dared to make it--to use it...."

"Antony Ferrara--"

"We knew he was here, boy; now we know that he is using his powers
here. Something tells me that we come to the end of the fight. May
victory be with the just."

CHAPTER XXI

THE MAGICIAN

Half-Moon Street was bathed in tropical sunlight. Dr. Cairn, with his
hands behind him, stood looking out of the window. He turned to his
son, who leant against a corner of the bookcase in the shadows of the
big room.

"Hot enough for Egypt, Rob," he said.

Robert Cairn nodded.

"Antony Ferrara," he replied, "seemingly travels his own atmosphere
with him. I first became acquainted with his hellish activities during
a phenomenal thunderstorm. In Egypt his movements apparently
corresponded with those of the _Khamsin_. Now,"--he waved his hand
vaguely towards the window--"this is Egypt in London."

"Egypt is in London, indeed," muttered Dr. Cairn. "Jermyn has decided
that our fears are well-founded."

"You mean, sir, that the will--?"

"Antony Ferrara would have an almost unassailable case in the event
of--of Myra--"

"You mean that her share of the legacy would fall to that fiend, if
she--"

"If she died? Exactly."

Robert Cairn began to stride up and down the room, clenching and
unclenching his fists. He was a shadow of his former self, but now his
cheeks were flushed and his eyes feverishly bright.

"Before Heaven!" he cried suddenly, "the situation is becoming
unbearable. A thing more deadly than the Plague is abroad here in
London. Apart from the personal aspect of the matter--of which I dare
not think!--what