"Gee whiz!" whispered Charley. "It's like going to an aquarium and looking at the fish in glass cages. I never dreamed a brook could be so interesting." With the utmost caution they moved along the bank of the run, looking for crayfish of suitable size. Whenever they found one, Charley focused the flash-light on it, moving the beam so as to dazzle the creature and keep the space behind it in darkness. And Lew would slip the coffee-pot into the water and move it cautiously up to the crayfish, ready for a final, quick scoop. Sometimes he was successful and sometimes the intended victim escaped. Always the click of the metal pot against the stony bottom sent the little creatures in the water scurrying for cover. A second after Lew tried for the crayfish not a living thing was visible. So it was necessary to move on along the stream. From spot to spot the two boys proceeded, now getting a good bait, now missing one, but ever keenly enjoying the wonderful glimpses of the life in the brook. So they continued until they had a goodly number of crayfish. "I believe that's enough," said Lew. "Let's get back to camp. The fellows will be at their instruments at nine, ready to talk to us." He glanced at his watch. "I had no idea," he cried, "that it was so late. It's almost nine now. We'll have to hurry." So fascinating had been the glimpses of life in the brook that time had sped much faster than either boy realized. They hurried back to their camp. They had taken the precaution to sling their grub high above ground on a piece of wire, but apparently nothing had tried to molest anything. Lew rekindled the fire in the little stone fireplace they had built and Charley uncovered the wireless instruments and sat down on one pack bag. The other he flung to Lew. Then he slipped the receivers on his head, threw over his switch, and sent the bright sparks flashing between the points of his spark-gap. "CBWC--CBWC--CBWC--CBC," he rapped out. (Camp Brady Wireless Club, Charley Russell calling.) Then he sat in silence, waiting for an answer. It came promptly. "CBC--CBC--CBC--I--I--I--GA." (Charley Russell--We're here. Go ahead.) "Got 'em," he cried. He answered and got a reply. "They want to know why we didn't call up last night," Charley said to Lew. The fire in the little fireplace burned clear and bright, making a circle of light in the dark forest. Lew sat near the fire, cross-legged on his pack bag, thrusting an occasional stick into the flames. Charley sat by his instrument. Rapidly he pressed the key, and the sparks flew between the points of his gap like tiny flashes of horizontal lightning. "Hello! Is that you, Willie?" rapped out Charley. "Sure," came the answer. "But we're all here. Why didn't you call up last night?"