"You have got it. You have certainly got it." Laroche was more
enthusiastic than the inspector had before seen him. "It's what you call
a cute scheme, quite on par with the rest of the business. They didn't
leave much to chance, these! And yet it was this very precaution that
gave them away."

"No doubt, but that was an accident."

"You can't," said the Frenchman sententiously, "make anything completely
watertight."

The next night they went out to the clearing, and as soon as it was dark
once more entered the shed. There with more powder--white this time-they
tested the tank lorry for finger-marks. As they had hoped, there were
several on the secret fittings, among others a clear print of a left
thumb on the rivet head of the spring.

A moment's examination only was necessary. The prints were those of M.
Pierre Raymond.

Once again Inspector Willis felt that he ought to have completed his
case, and once again second thoughts showed him that he was as far away
from that desired end as ever. He had been trying to find accomplices
in the murder of Coburn, and by a curious perversity, instead of finding
them he had bit by bit solved the mystery of the Pit-Prop Syndicate. He
had shown, firstly, that they were smuggling brandy, and, secondly, how
they were doing it. For that he would no doubt get a reward, but such
was not his aim. What he wanted was to complete his own case and get the
approval of his own superiors and bring promotion nearer. And in this he
had failed.

For hours he pondered over the problem, then suddenly an idea which
seemed promising flashed into his mind. He thought it over with the
utmost care, and finally decided that in the absence of something better
he must try it.

In the morning the two men travelled to Paris, and Willis, there taking
leave of his colleague, crossed to London, and an hour later was with
his chief at the Yard.

CHAPTER 19. WILLIS SPREADS HIS NET

Though Inspector Willis had spent so much time out of London in his
following up of the case, he had by no means lost sight of Madeleine
Coburn and Merriman. The girl, he knew, was still staying with her aunt
at EASTBOURNE, and the local police authorities, from whom he got
his information, believed that her youth and health were reasserting
themselves, and that she was rapidly recovering from the shock of her
father's tragic death. Merriman haunted the town. He practically lived
at the George, going up and down daily to h