while I speak."

"Eat awa'," assented the other, while he lit a corn-cob pipe to satisfy
his own immediate wants. "There's plenty mair where that came frae, and
the coffee will soon be ready!"

Arnold then launched into a brief recital of his and his chum's
adventures, beginning with the departure of their fathers on the
previous morning, and concluding--

"So all this afternoon we've been wandering about trying to find a path
back to our camp, so as to start afresh by the river course. But it was
no use."

"And we might have been wandering still if it had not been for a strange
accident that led us here," added Alf, at which remark Mackintosh
questioned--

"And what might that be? The soond o' Haggis's nightingale voice?"

"No--at least, not in the first place. We heard that later. What first
started us in this direction was a curious sort of light that we
discovered on one of the trees. And while we were examining it we
noticed that there were other lights on other trees in a straight line
with one another. Strange, wasn't it?"

"Very," returned the Scotsman dryly. "Very strange."

"It would be a good thing for a naturalist," said Bob. "I noticed that
there was a perfect cloud of moths flying about wherever there was a
patch of light. A collector of moths and butterflies would reap a
harvest. I suppose you've noticed the lights as well as we?"

"H'm--yes--considering that I painted the trees mysel' this afternoon,"
was the reply. "It's an invention o' my own. I'm what _you_ call a
collector of moths and butterflies. An entomologist is a shorter way o'
putting it. Well, there's many folks stick to treacle--I mean, stick to
the auld-fashioned way o' putting dabs of treacle and speerit on trees
to attract the nocturnal creatures. That's all very fine and good. But
you canna carry gallons o' treacle on a tramp like this, when your whole
outfit must be packed on one pony. So says I to mysel': 'Moths are
attracted by light; I must invent a composeetion o' phosphorus to take
the place o' treacle.' And those lights that you found on yon trees are
the result."

"And a splendid idea it is!" exclaimed Alf, who had also done his little
share of treacling at school. "Is it a success?"

"Magnificent. I've found more moths than were known to exist in the
West. I'm thinking that I'll open the eyes o' the Royal Edinburgh
Entomological General Natural History Exchange Society when I get back
again after my journeys. But--