ing your grounds to
take a picture of your house," he started to say. "We didn't mean any
harm, and will go away at once, sir."

The man looked sternly at Frank, but the boy noticed with a feeling of
relief that the half upraised stick was slowly lowered. Apparently
something influenced Aaron Dennison to decide not to take the law into
his own hands, and use that heavy cane on these rash intruders.

"How did you get in here?" he demanded abruptly.

"There is a board loose on the fence, sir, and we couldn't resist the
temptation to come through. My chum here is making a hobby of taking
pictures, and he wanted one of your house, because it was so peculiar
in its build. I hope you won't think too badly of us for intruding."

Aaron Dennison did not take any notice of this last remark; but
apparently he caught some meaning back of Frank's words.

"How did you know my house differed from any other one; have you been
in here before this?"

Evidently the discreet old housekeeper had decided not to tell of the
former visit of the boys, and it was Frank himself who had given the
secret away. He determined not to evade the issue, but continue to be
frank with the irate gentleman.

"Yes, sir," he said, steadily. "I wandered up this way yesterday, and
saw the house. It was because I was so enthusiastic in my description
that Will here wanted to come and get a picture of it."

"So as to tell every one, I suppose, that it is the secluded home of
the eccentric old hermit, as I believe they call me in the towns where
my men trade," the other continued with a half sneer. "But what are
you boys doing up in this section of the country? It is the first time
for a long while that I have seen a stranger about here."

"We are camping, sir, on the lake shore, and having a good time for a
few weeks, fishing, taking pictures, and all that. In our home town of
Centerville they call us the Outdoor Chums, because we love to camp
out."

"On the lake shore, you say?" repeated the other, looking keenly at
Frank. "Tell me, is your camp anywhere near Cabin Point?"

"Yes, we've gone to work, Mr. Dennison, and fixed the old cabin all
up; and it's there we're staying," Frank told him.

"I wonder--" began the other, frowning, "if you had anything to do
with startling me last night, when I was taking a walk down to the
lake, as I sometimes do when the spirit moves me. Do you know anything
about that frightful blinding flash that gave me such a s