"Then you think this would be a good time to take a room here? I am looking for one in this neighbourhood," said Dupré.
"You couldn't do better than arrange with M. Sonne. You could make a good bargain with him now, and you would be perfectly safe."
"I am glad that you mentioned it; I will speak to M. Sonne to-night, and see the rooms to-morrow. Have another sip of brandy?"
"No, thank you, I must be getting back to my place. Just tell M. Sonne, if you take a room, that I spoke to you about it."
"I will. Good-night."
Dupré paid his bill and tipped the garçon liberally. The proprietor was glad to hear of any one wanting rooms. It showed the tide was turning, and an appointment was made for next day.
Dupré kept his appointment, and the concierge showed him over the house. The back rooms were too dark, the windows being but a few feet from the opposite wall. The lower front rooms were too noisy. Dupré said that he liked quiet, being a student. A front room on the third floor, however, pleased him, and he took it. He well knew the necessity of being on good terms with the concierge, who would spy on him anyhow, so he paid just a trifle more than requisite to that functionary, but not enough to arouse suspicion. Too much is as bad as too little, a fact that Dupré was well aware of.
He had taken pains to see that his window was directly over the front door of the café, but now that he was alone and the door locked, he scrutinised the position more closely. There was an awning over the front of the café that shut off his view of the pavement and the policeman marching below. That complicated matters. Still he remembered that when the sun went down the awning was rolled up. His first idea when he took the room was to drop the dynamite from the third story window to the pavement below, but the more he thought of that plan the less he liked it. It was the sort of thing any fool could do, as the policeman had said. It would take some thinking over. Besides, dynamite dropped on the pavement would, at most, but blow in the front of the shop, kill the perambulating policeman perhaps, or some innocent passer-by, but it would not hurt old Sonne nor yet the garçon who had made himself so active in arresting Hertzog.
Dupré was a methodical man. He spoke quite truly when he said he was a student. He now turned his student training on the case as if it were a problem in mathematics.
First, the dynamite must be exploded inside the café. Second, the thing must be done so deftly that no suspicion could fall on the perpetrator. Third, revenge was no revenge when it (A) killed the man who fired the mine, or (B) left a trail that would lead to his arrest.