The story is about an amateur detective who uses some elementary geometric triangulation to foil an assassination. The last paragraph is a great touch, “Why, Governor, you’re giving me too much credit. It was worked out by one of the greatest detectives of all time, some two thousand years ago. His name was Euclid”

"Well, indeed," said the governor. "May I congratulate you, Mr. Morrison, on this interesting achievement in ballistics?"

"As there is no way of properly resenting an insult from a man in your position," said Morrison venomously, "I will reserve my answer to that outrageous suggestion."

"Meantime," put in Average Jones, "let me direct your attention to a simple mathematical formula." He drew from his pocket an envelope on which were drawn some angles, subjoined by a formula. Morrison waved it aside.

"Not interested in mathematics?" asked Average Jones solicitously. "Very well, I'll elucidate informally. Given a bullet hole in a telegraph pole at a certain distance, a bullet scar on an iron girder at a certain lesser distance, and the length of a block from here to Harrison Avenue--which I paced off while you were skillfully ordering luncheon, Waldemar--and an easy triangulation brings us direct to this room and to two fugitive gentlemen with whom I mention the hypothesis with all deference, Mr. Morrison, you are probably acquainted."

It appears that the OBB was first published under the title, "Flashlight" in a magazine called "Success" in April, 1911.