"I know." Roger was scanning the mud field to the northward.
"There must be high ground some place beyond," continued the engineer. "And if there is, there'll be a creek running into that mud. That would mean fresh water."
"I see something that looks like high ground, all right," said Payne, studying a smudge of blue against the northern horizon. "But I don't see anything like running water."
"It's got to be there," maintained Higgins. "In this soft mud it may be underground and you'd never see it."
Payne held his precarious perch, scrutinizing the treacherous ground which they must cross if they were to continue their journey, until the sun, like a blazing red wafer, had slipped down behind the mangrove swamp in the west and darkness had come to the earth below. The darkness spread and crept upward to where he sat, and as he prepared to descend Payne glanced up toward the last rosy gleams on the topmost branches of the tall, dead tree. The buzzards, which had flown away at his appearance, had returned and the sun was gilding their black bodies and their foul red heads, as patiently, confidently, they sat waiting.
"Higgins," said Payne, when he reached the ground, "there seems to be a chain of islands running across that mud. I picked out a string of them. The first one is out there about a hundred yards away, and I believe that's about the average distance between them. If we can dope out some scheme for getting across a hundred yards of that mush at a time I believe we can make it. That mud doesn't run on forever; I'm sure I saw solid ground with timber on it to the north."
"How far away?"
"It's impossible even to guess at the distance in that light. I'll go up in the morning and have another look."
"Do the islands look solid?"
"There's brush on them; that's all I could see."