ad
taken an interest in developing and printing, made a 10 by 14-inch
enlargement of each. They spent most of Thursday studying them,
talking over their various clues endlessly, and waiting for Cap'n
Mike's call. Shortly after supper on Thursday night he did call, but
only to say he had nothing to report and that he hadn't been able to
talk to Jim Killian. The fisherman was taking a few days off to visit
his mother in Pennsylvania.

"A fine time for him to go vacationing," Rick said, "when he might be
able to supply some essential information. I've got an idea, Cap'n,"
he added. "Can you find out what source the automatic light uses for
electricity? See if it has its own power plant or whether there's a
cable that runs along the reef. If there is, see if there's a junction
box or a switch or anything."

Cap'n Mike promised to have the information next time he called.

They were too restless to sit still and read. Rick had thought about
asking his father to help him check the infrared spotlight in the lab,
but Hartson Brant was preoccupied with a scientific analysis problem,
so Rick decided to check his new invention by actual use.

Dismal was the subject. The boys took him for a walk to the backside
of the island where there was no light at all except for dim
moonlight. Scotty carried the power supply on a strap over his
shoulder while Rick carried the camera and its attachments. The thing
was uncanny, even when its operation was understood. To the naked eye,
Dismal was just a vague blur under the trees. But with the infrared
searchlight on him, Rick could see him through the telescope as though
it were white light. He shot a few feet of film, then took it to the
photo lab. He could develop short lengths by dipping them into bottles
of solution, although full lengths would have to go to a New York lab
for processing.

Projecting the test length cleared up his questions. The camera worked
beautifully at distances up to three hundred yards. Beyond that,
although things still could be seen, the lighting was poor and
definition hazy.

He spent more time in the darkroom winding the infrared film on
hundred-foot rolls and placing them in light-tight cans, then he
reloaded the camera with a full spool. That done, there was nothing to
do but wait and try to read.

On Friday night, Scotty glanced up from the leather chair in Rick's
room. "What time is it?"

Rick was lying on the bed, studying the ceiling and working o