It had
evidently been around a small box or bottle. The address was evidently
that of some firm doing business in some town in New York State. What
the "ark" could stand for, he could not surmise.

As the detective left the Bardon house, he saw a middle-aged man
entering the Langmore mansion. The man was well dressed and carried a
dress-suit case.

"A visitor of some sort," he mused. "Perhaps a relative."

When he stepped up on the piazza Raymond Case came out to meet him.
The young man wished to know if he had learned anything from the doctor.

"Not a great deal," answered Adam Adams. "Who was that man who just
came in?"

"Thomas Ostrello, one of Mrs. Langmore's sons by her first husband."

"Is he a frequent visitor here?"

"I believe not. He is a commercial traveler, and on the road nearly
all the time."

"Has he been here since the tragedy?"

"No. He was here the day before it occurred, but went away in the
evening. I suppose his mother's death has shocked him a good deal."

"I believe you said the Ostrellos are not well off?"

"No; they are poor, so Margaret told me. Both of the sons are on the
road, one for a paint house and this one for a drug house. By the way,
I am going to town, to see the coroner. Do you want to come along?"

"No, I'll see him later. I want to take a walk around this place
first. I may pick up a stray clue."

Left to himself, Adam Adams walked slowly around the mansion, noting
the several approaches. He looked in at the stable and the automobile
shed, and strolled down to the brook. He made no noise, for it was his
practice to move about as silently as possible and without attracting
attention.

Suddenly he halted and stepped out of sight behind some bushes not far
away from the brook. He heard a splashing, which told him that
somebody was near.

CHAPTER V

THE MAN AT THE BROOK

Beside the brook stood a shabbily-dressed man, apparently fifty-five or
sixty years old. He wore an old rusty black coat and a soft hat with a
hole in it. His face was tanned and partly covered with a beard.

The man was acting in a manner to excite anybody's curiosity. He
carried a stick in his hand, and was poking around in the water with
it. Every once in a while he looked around, to see if anybody was
observing him.

Straining his eyes, Adam Adams saw a strip of white floating on the
water. Once or twice it disappeared. Finally the end of the strip
caught on an