“If you can prove that already, your police must beat ours hollow,” said Caerleon. “Let us hear about it.” “In the first place, your Majesty, I have been examining the ruins, with the aid of a detachment of sappers. We were searching for the crown jewels--which are now, alas! shapeless lumps of metal, their precious stones for the most part calcined--and we found distinct traces of petroleum in more than one spot. Does not that fact speak for itself? Petroleum is never used in lighting the chapel, and it is a favourite weapon of incendiaries. Upon making this discovery, I proceeded to interrogate the guard, who were all under arrest. Those who were posted at the gates last night were unanimous in declaring that no unauthorised person had passed in after the workmen had departed, with the exception of one woman, who said that she was the mother of one of the decorators employed, and that her son had left behind him his book of gold-leaf, which she had come to fetch. The sentries describe her as very old and bent, but with piercing dark eyes,--and wearing the dress of the respectable artisan class. The acting master of the household had not yet locked the chapel doors, and the woman was therefore allowed to go in and look for the book, which took her some time to find. She came out with it in her hand, and the door was immediately locked. The theory is that she carried in with her a supply of petroleum in a can----” “Or perhaps in bladders hung round her waist, as brandy used to be smuggled into England,” put in Cyril, who had been following the details with much interest. M. Drakovics bowed. “Very possibly, milord. Having saturated the woodwork behind the screen of the sanctuary with the oil, she would arrange a slow match which would not come in contact with it for some hours, and would then take her departure, provided with a book of gold-leaf to deceive the guard. The master of the household, looking in from the doorway, would notice nothing, and would lock the door and take away the key, leaving the match to do its work.” “But why may not the culprit be the woman she gave herself out to be?” asked Caerleon. “Because, your Majesty, the woman’s son and the other members of her family are all able to swear that from nine to ten o’clock, the hour at which the incendiary did her work, Nicola Stanovics’s mother was engaged in a violent quarrel with her daughter-in-law, who had left her infant at home while she went out to see the illuminations. The old woman met her at the door as she returned, and their dispute almost ended in blows. Moreover, the guard, when confronted with Marynia Stanovics, declared without hesitation that she was not the woman whom they had admitted.” “Well, that seems to clear the old lady, at any rate,” said Caerleon. “Your work has been most successful in a negative direction. Have you any positive clue to go upon?”