“Wait - what’s in that dip over there?” said Dick, pointing to where the ground seemed to dip downwards. “It looks like another old quarry, rather like the one we’re camping in, but smaller, much smaller. I bet that’s where the fire was!”

They made their way to the quarry. It was much more overgrown than theirs was, and was evidently one that had been worked at an earlier time. It dipped down to quite a pit in the middle and set there was something unusual. What was it?

The boys scrambled down into the pit-like quarry and made their way to the middle. They stared at the big thing that was set there, pointing to the sky.

“It’s a lamp, a powerful lamp of some kind,” said Dick. “Like those we see making a flare-path at an aerodrome, guiding planes in to land. Fancy seeing one here!”

“How did the gypsies get it?” wondered Dick, puzzled. “And why signal to a plane that doesn’t land? It looked as if it wanted to, circling round low like that.”

“Maybe the gypsies signalled that it wasn’t safe to land for some reason,” said Julian. “Or perhaps they were going to give something to the pilot and it wasn’t ready.”

“Well, it’s a puzzle,” said Dick. “I can’t imagine what’s going on. Something is, that’s certain. Let’s snoop round a bit.”

They found nothing else, except a trail that led to the lamp and back. Just as they were examining it, a shout came to their ears. They swung round - and saw the figure of a gypsy at the edge of the pit.

“What are you doing here?” he shouted, in a harsh voice. He was joined by a few others, and they all looked threateningly at Julian and Dick as they climbed out of the pit.

Julian decided to be honest. “We’re camping out on the moor for a night or two,” he said, “and we heard a plane last night, circling low. We also saw a glow that appeared to be guiding it, and we came along to see what it was. Did you hear the plane?”

“Mebbe we did and mebbe we didn’t,” said the nearest gypsy, who was Sniffer’s father. “What of it? Planes fly over this moor any day!”

“We found that powerful lamp,” said Dick, pointing back at it. “Do you know anything about that?”

“Nothing,” said the gypsy scowling. “What lamp?”

“Well, as far as I can see there’s no charge for looking at it,” said Julian. “Go and have a squint, if you don’t know anything about it! But I can’t believe that you didn’t see the light it gave last night! It’s a jolly good place to hide it, I must say.”

“We don’t know anything about any lamp,” said another gypsy, the old one with grey hair. “This is our usual camping-place. We don’t interfere with anything or anybody - unless they interfere with us. Then we make them sorry for it.”