That which Gilles de Laval shrank from confessing was that he sought the Philosophical Stone in the blood of murdered children, and that it was covetousness which drove him to this monstrous debauchery. On the faith of his necromancers, he believed that the universal agent of life could be suddenly coagulated by the combined action and reaction of outrage on Nature and murder. He collected afterwards the iridescent film which forms on blood as it turns cold;[213] he subjected it to various fermentations, digested the product in the philosophical egg of the athanor, combining it with salt, sulphur and mercury. He had doubtless derived his recipe from some of those old Hebrew Grimoires which, had they been known at the period, would have been sufficient to call down on Jewry at large the execration of the whole earth. Persuaded, as they were, that the act of human impregnation attracts and coagulates the Astral Light in its reaction by sympathy on things subjected to the magnetism of man, the Israelitish sorcerers had plunged into those enormities of which Philo accuses them, as quoted by the astrologer Gaffarel.[214] They caused trees to be grafted by women, who inserted the graft while a man performed on their persons those acts which are an outrage to Nature. Wherever Black Magic is concerned the same horrors recur, for the spirit of darkness is not one of invention. Gilles de Laval was burned alive in the _pré de la Magdeleine_, near Nantes; he obtained permission to go to execution with all the pageantry that had accompanied him during life, as if he wished to involve in the ignominy of his punishment the ostentation and cupidity by which he had been so utterly degraded and lost so fatally.[215] CHAPTER VII SUPERSTITIONS RELATING TO THE DEVIL