Doctor Wood. Modern Wizard of the Laboratory: The Story of an American Small Boy Who Became the Most Daring and Original Experimental Physicist of Our Day-but Never Grew Up

Lieutenant Itzel and Detective Schalter of the Baltimore police department, who had active charge of the case, after they’d been called in to help the local constabulary, as Scotland Yard is called to rural districts in England, soon learned that Naomi Hall had been pregnant, and this circumstance, if not a clue, offered at least a first lead to work on. But here, almost immediately, the police came to a sort of double impasse. Naomi Hall had been for some time lawfully married to Herman Brady, a young farmer of the county. The marriage was on record, the young couple were on good terms, as far as anybody knew, and the marriage had been kept a secret from the two families only because Mrs. Brady, Herman’s mother, had opposed it. It meant more mouths to feed. Herman was working his mother’s farm. She was dependent on him, and he hadn’t wanted to tell her about the marriage until he was in a better position to take care of them both. The first impasse confronting the police was the seeming lack of any urgent motivation for murder, even though a baby was expected in a few months. The second impasse was that Herman Brady, a hulking dirt farmer and not a very bright one at that, knew nothing whatever about machinery, mechanics, explosives — never tinkered with gadgets — had never done so in earlier boyhood — had no mechanical ingenuity whatever — couldn’t even mend a broken plow — in short could no more have constructed an infernal machine than have built a rocket to the moon! Of this, the police were absolutely sure, and it turned out they were right.

Everybody agreed that Herman was too dumb to have done it.

“Now if it had been his brother… if it had been Leroy”, said farmers, gossiping around the stove in the general store at Seat Pleasant. “And what about his brother?” the police were soon inquiring. Well, Leroy Brady was the opposite of Herman, they said. Just one of those differences that happen in so many families. Leroy was a sort of mechanical genius. But he was out of the picture. He worked, and lived, in Washington, had a good-looking young wife of his own, saw little of his mother and Herman — probably hadn’t even known Naomi Hall at all. Leroy worked in a big Chevrolet garage — headquarters of the Chevrolet in Washington — and was one of the best mechanics they had. He was known to have displayed great ingenuity in devising mechanical contraptions, including a device for the opening and closing of doors.

The police weren’t quite so sure, when they looked into it, that Leroy was “out of the picture”. Yet they could discover no earthly connection or reason for Leroy Brady to have murdered Naomi Hall — except as a farfetched “favor” to his brother — and what had been learned up to then by examination and analysis of the bomb debris and fragments held nothing which pointed to their having come from any garage, much less any particular one. Steel fragments picked up in the bomb crater had been sent to the Bureau of Standards and the Bureau of Mines. The government experts’ conclusions were that the firing mechanism had been roughly similar to that which creates the spark in an ordinary cigarette lighter, and that this had been attached by a tiny chain (passing through a tube) to the lid of the box. The explosive material, they believed, might have been acetylene. In moistening one of the fragments which had a white deposit on it, they had discerned an acetylene odor. (Acetylene was already long outmoded in 1930 for motor headlights, and pointed no longer particularly to a garage as it might have in the old first days of the Model T.)

The detectives had nothing whatever on Leroy Brady beyond the fact that he had the mechanical ingenuity to have devised the bomb — and was Herman’s brother. So they were again at an impasse.

Dr. Wood, Johns Hopkins’s great experimental physicist, was called in as a police consultant on the suggestion of Governor Ritchie. The suggestion was welcomed by District Attorney Parran and the police. Dr. Wood began to work directly with Lieutenant Itzel and his department.

They handed over to me immediately (says Dr. Wood) the small steel fragments which had been found in the crater under the floor of the Hall house, and which in the meantime had been returned to them by the Bureau of Standards. Then, very sensibly, they drove me down to the scene of the explosion, which I studied thoroughly. Everything pointed to dynamite. There was a hole about eighteen inches in diameter in the kitchen table and directly below it a hole through the floor nearly three feet in diameter. I came to the conclusion that the damage could be best accounted for by about half a stick of dynamite. Acetylene, I knew, could not have done it. Then, back at Johns Hopkins, in my laboratory, I began to examine the steel fragments.