ey found themselves on the brink of a gully a
hundred yards in width; and Payne, driving ahead at full speed, cried
out in anguish as he realized how they were stopped.

"Hold on," said Higgins. "That ground on the other side is higher, and
it looks to me like a different formation. Yes; it's limestone with
sand on top. Cheer up!"

Payne threw a dry branch onto the mud and it sank immediately. Wearily
he turned at right angles to the trail and led the way in a search for
the end of the gully. For a mile they followed the barrier of mud,
then Higgins called a halt. "Look at this formation." He pointed to a
slight swell in the level monotony of the swamp. "If that showed in
any human country I'd say it was the beginning of a little ridge."

The slight rise ran to the edge of the gully, where it was broken, and
appeared again on the farther side of the mud.

"There's just a chance that it runs right through that mud," Higgins
was probing into the slime with a broken branch. "Yep. Here it is,
about five feet down. Ugh! Pretty little piece of wading, but unless
I miss my guess it will be miles before we find another fording place
through that mud. Wish Willy High Pockets was here. He's the boy who
could show us how."

Payne looked at the span of slime between the banks.

"Do you think we'll be through if we get to the other bank?" he asked.

"Sure. This mess can't last forever. Hold on." Payne had stepped off
into the breast-high mud. "What are you going to do?"

"See if this shallow runs all the way across."

"No you don't! Chances are there's a break in it in the middle and
then you'd be all out of luck. I'll do the investigating."

"Stay right where you are; I'm boss." Payne was forcing his way out
from shore. Halfway across he stopped, panting and exhausted from the
task of driving through the clinging mud.

"No break?" called Higgins.

"No; solid so far."

"Then it's solid all the way across." Higgins leaped in and, profiting
by the trail broken in the mud, came swiftly up to where Roger stood,
took a desperate chance and fairly swam through the mud, and took the
lead.

"I'll break trail the rest of the way. Now--both together!"

Pushing, pulling, falling and floundering they thrust on. The mud grew
thicker, heavier, and each step in it now was an appalling effort. At
last Higgins came to a stop. They were twenty feet from the farther
bank and the mud had assumed the consiste