e
mystery, but I confess I leaped at the idea of coming back in order to
meet you again, and on the understanding that there was to be nothing in
the nature of spying, I agreed to his proposal."

Merriman paused, but the girl, whose eyes were fixed intently on his
face, made no remark, and he continued:

"While we were here, Hilliard, who is very observant and clever, saw one
or two little things which excited his suspicion, and without telling
me, he slipped on board the Girondin and overheard a conversation
between Mr. Coburn, Captain Beamish, Mr. Bulla, and Henri. He learned at
once that something serious and illegal was in progress, but he did not
learn what it was."

"Then there was spying," she declared accusingly.

"There was," he admitted. "I can only say that under the circumstances
he thought himself justified."

"Go on," she ordered shortly.

"We returned then to England, and were kept at our offices for about a
week. But Hilliard felt that we could not drop the matter, as we should
then become accomplices. Besides, he was interested. He proposed we
should try to find out more about it. This time I agreed, but I would
ask you, Madeleine, to believe me when I tell you my motive, and to
judge me by it. He spoke of reporting what he had learned to the police,
and if I hadn't agreed to help him he would have done so. I wanted at
all costs to avoid that, because if there was going to be any trouble I
wanted Mr. Coburn to be out of it first. Believe me or not, that was my
only reason for agreeing."

"I do believe you," she said, "but finish what you have to tell me."

"We learned from Lloyd's List that the Girondin put into Hull. We went
there and at Ferriby, seven miles up-stream, we found the depot where
she discharged the props. You don't know it?"

She shook her head.

"It's quite like this place; just a wharf and shed, with an enclosure
between the river and the railway. We made all the inquiries and
investigations we could think of, but we learned absolutely nothing. But
that, unfortunately, is the worst of it. Hilliard is disgusted with our
failure and appears determined to tell the police."

"Oh!" cried the girl with an impatient gesture. "Why can't he let it
alone? It's not his business."

Merriman shrugged his shoulders.

"That's what he said at all events. I had the greatest difficulty in
getting him to promise even to delay. But he has promised, and we have
a month to make our plans. I