Porhoet was changed among his books. Though he preserved the
amiable serenity which made him always so attractive, he had there a
diverting brusqueness of demeanour which contrasted quaintly with his
usual calm.

'I was telling these young people, when you came in, of an ancient Koran
which I was given in Alexandria by a learned man whom I operated upon for
cataract.' He showed her a beautifully-written Arabic work, with
wonderful capitals and headlines in gold. 'You know that it is almost
impossible for an infidel to acquire the holy book, and this is a
particularly rare copy, for it was written by Kait Bey, the greatest of
the Mameluke Sultans.'

He handled the delicate pages as a lover of flowers would handle
rose-leaves.

'And have you much literature on the occult sciences?' asked Susie.

Dr Porhoet smiled.

'I venture to think that no private library contains so complete a
collection, but I dare not show it to you in the presence of our friend
Arthur. He is too polite to accuse me of foolishness, but his sarcastic
smile would betray him.'

Susie went to the shelves to which he vaguely waved, and looked with a
peculiar excitement at the mysterious array. She ran her eyes along the
names. It seemed to her that she was entering upon an unknown region of
romance. She felt like an adventurous princess who rode on her palfrey
into a forest of great bare trees and mystic silences, where wan,
unearthly shapes pressed upon her way.

'I thought once of writing a life of that fantastic and grandiloquent
creature, Philippus Aureolus Theophrastus Paracelsus Bombast von
Hohenheim,' said Dr Porhoet, 'and I have collected many of his books.'

He took down a slim volume in duodecimo, printed in the seventeenth
century, with queer plates, on which were all manner of cabbalistic
signs. The pages had a peculiar, musty odour. They were stained with
iron-mould.

'Here is one of the most interesting works concerning the black art.
It is the _Grimoire of Honorius_, and is the principal text-book of all
those who deal in the darkest ways of the science.'

Then he pointed out the _Hexameron_ of Torquemada and the _Tableau de
l'Inconstance des Demons_, by Delancre; he drew his finger down the
leather back of Delrio's _Disquisitiones Magicae_ and set upright the
_Pseudomonarchia Daemonorum_ of Wierus; his eyes rested for an instant on
Hauber's _Acta et Scripta Magica_, and he blew the dust carefully off the
most famous, the mos