fought, and died. From the old guns and other evidences we found near
them we know that all this happened at least fifty years ago, and
perhaps more. But--"

He paused, whistling softly.

"Where is the third waterfall?"

"I thought we settled that last winter," replied Rod, a little
irritated by his companion's doubt. "If writing goes for anything,
Ball was a man of education, and he drew the map according to some
sort of scale. The second fall is only half as far from the first fall
as the third fall is from the second, which is conclusive evidence of
this. Now Mukoki discovered the first waterfall fifty miles down the
chasm!"

"And we figured from the distances between John Ball's marks on the
birch, that the third fall was about two hundred and fifty miles from
our old camp at the head of the chasm," rejoined Wabigoon. "It looks
reasonable."

"It is reasonable," declared Rod, his face flushed with excitement.
"From the head of the chasm our trail is as plain as day. We can't
miss it!"

Mukoki had been listening in silence, and now joined in the
conversation for the first time.

"Must get to chasm first," he grunted, giving his shoulders a hunch
that suggested a great deal.