"You mean that young Floyd planned to burn up the will which left him a pauper, so that he might obtain his interest as heir-at-law?"
"That's the motive you were asking for when Costa interrupted us. It was clumsily done, wasn't it? But not so clumsily, when you look at it further. The professor kept his valuables in an iron lock-box which he called a safe. To blow it open was dangerous, unless"—McCausland paused to drive his meaning home—"unless the sound of the explosion could be smothered in the general confusion of a fire."
"You attribute the explosions to——"
"Placed the charge himself in a wooden box under the safe. Told Bertha a plausible story to provide against discovery."
"Six human lives to pay for a few paltry dollars."
"Five million dollars! The professor must have left nearly ten and Floyd would have shared them equally with the other nephew. Hardly a paltry figure, $5,000,000! I've seen murder committed for a 10-cent piece."
"But that was manslaughter in the heat of a quarrel."
"To be sure; and by expert Sicilian carvers, with magnifying-glass eyes and tempers formed between Etna and Vesuvius. But $5,000,000 is a fortune, Bigelow."
The district attorney paced up and down, meditating. At last he turned and brought his fist down on the table so hard that the bloodhound bayed.
"This is murder as well as arson. I want that understood."