le
working in his secret laboratory at the sublimation of the deadly
poison, accidentally dropped the mask of glass which protected his face.
He inhaled the noxious fumes and fell dead by the side of his crucibles.
This event gave Desgrais, captain of the police of Paris, a clue to the
horrors which had so long baffled his pursuit.

The correspondence of St. Croix was seized. His connection with
the Marchioness de Brinvilliers and his relations with Exili were
discovered. Exili was thrown a second time into the Bastile. The
Marchioness was arrested, and put upon her trial before the Chambre
Ardente, where, as recorded in the narrative of her confessor, Pirol,
her ravishing beauty of feature, blue eyes, snow-white skin, and gentle
demeanor won a strong sympathy from the fickle populace of Paris, in
whose eyes her charms of person and manner pleaded hard to extenuate her
unparalleled crimes.

But no power of beauty or fascination of look could move the stern La
Regnie from his judgment. She was pronounced guilty of the death of her
husband, and sentenced first to be tortured and then beheaded and her
body burnt on the Place de Greve, a sentence which was carried out to
the letter. The ashes of the fairest and most wicked dame of the Court
of Lous XIV. were scattered to the four corners of the city which had
been the scene of her unparalleled crimes. The arch-poisoner Exili was
also tried, and condemned to be burnt. The tumbril that bore him to
execution was stopped on its way by the furious rabble, and he was torn
in pieces by them.

For a short time the kingdom breathed freely in fancied security; but
soon the epidemic of sudden as well as lingering deaths from poison
broke out again on all sides. The fatal tree of the knowledge of evil,
seemingly cut down with Exili and St. Croix, had sprouted afresh, like a
upas that could not be destroyed.

The poisoners became more numerous than ever. Following the track of
St. Croix and La Brinvilliers, they carried on the war against
humanity without relaxation. Chief of these was a reputed witch and
fortune-teller named La Voisin, who had studied the infernal secret
under Exili and borne a daughter to the false Italian.

With La Voisin were associated two priests, Le Sage and Le Vigoureux,
who lived with her, and assisted her in her necromantic exhibitions,
which were visited, believed in, and richly rewarded by some of the
foremost people of the Court. These necromantic exh