He raised his arm to blow the whistle that would begin the swimming period, and Sherlock made sure that Wally Rawn, at least, had no tattooed eagle on his left arm. The dock was now crowded with campers, and the shrill call had no sooner sounded than the air was full of diving bodies and splashing spray as the boys of Lenape took to water. The life-saving boats were now at their posts, guarding the safety of the swimmers.
Sherlock remained on the dock, where he had a full view of everyone. His head jerked back and forth as he tried to follow every move of the group of swimming boys, now grown to almost the full number of the camp. He caught sight of Jerry and Jake Utway, whose flying bodies curved through the air from the highest diving-platform and almost at the same instant cleft the rippling surface of Lake Lenape. He watched them moodily as they swung hand over hand toward the farthest lifeboat. At any rate, neither of them bore a tattooed eagle on his arm! He must find the mysterious accomplice. With renewed energy he swept the sportive, glistening bodies of the gay swimmers with an intent gaze.
When the final “All out!” whistle blew, the dejected Sherlock made his way up the hill. He was baffled. His vigil had not revealed an incriminating tattoo-mark on the arm of any of the campers or leaders present. He must be patient and watchful, trusting to luck and his skill at shadowing the suspected twins to bring forth some fresh clue.
As he entered Tent Ten, the only one of his comrades before him was little shock-headed Pete Lister, youngest and smallest lad in the tent-group. The kid looked up as Jones came up the step.
“Hey, Sherlock, look what I’m doing!” He squirmed over in his seat on the unmade bunk, and waved an indelible pencil in the air. “See? Making pictures, I am! Bet you never thought of this, Sherlock!” He stuck out one sunburnt leg. The calf and thigh were a mass of scrawled, deep-purple designs—crooked anchors, shaky outlines of American flags, hearts, daggers, skulls, and Pete’s own name in wavering characters. “You don’t need to worry—they come off easy. See? First you draw ’em, then you wet the picture a little, and I’ll bet you couldn’t tell ’em from a real tattoo-mark! Want to try it?”