"Far from it. I have to determine the effective range, then I have to run a couple of tests to find out what exposure I have to use, and then I have to find the field of vision of the telescope as compared with the field of the lens. A lot depends on the speed of the film emulsion. That will limit the range. The searchlight is effective at eight hundred yards, but I'll be lucky if I can get a picture at a quarter of that."
"Where did you get the sniperscope?" Scotty wanted to know.
"By mail. I read an ad in a magazine that advertised a lot of surplus war equipment, including this."
"You might have said something about it," Scotty reproached.
Rick grinned. "You were too busy working on the motorboats. I knew you couldn't have two things on your mind at once."
Since the boys returned from vacation, Scotty had been overhauling the engines on the two motorboats which were used, along with Rick's plane, for communication with Whiteside, the nearest town on the mainland.
"I have a book downstairs that you'll find useful, Rick," Hartson Brant said. "It gives the comparative data on lenses. It may save you some figuring."
"Thanks, Dad," Rick replied. "I may have to ask your help in working out the mathematics, too. Anyway...." He stopped as the phone rang.
In a moment Mrs. Brant called. "Jerry, it's your paper."