“I wouldn’t know,” returned Mr. Brewster. “As you say, I am only interested in rubber. And it’s time that I was starting off to look for some.”
With that parting, Mr. Brewster motioned his companions back toward the main trail. They had only gone a dozen paces, when Mr. Brewster undertoned:
“Take turns glancing back to see what that crowd is doing. I don’t trust any of them, particularly Urubu.”
Biff took the first look and reported that Urubu, like Serbot and Pepito, was leaning on his gun while the trio apparently discussed what to do next. Soon Kamuka reported the same thing. Then Mr. Whitman looked back and announced that the group was now out of sight.
Mr. Brewster called for a quicker pace, and when they reached the main trail, they moved even faster—so fast in fact, that Biff and Kamuka had to jog along to keep up with the three men.
“We came back to look for you at dawn,” Biff’s father told the boys, “so our bearers will be packed and waiting for us when we reach our last night’s campsite. If Serbot pushes his crew to overtake us, they will be worn out, while we’ll be starting fresh.”
Mr. Whitman was feeling the heat, for he removed his white helmet to mop his forehead.
“More likely,” he said, “Serbot will try to overtake Nara by going up the bank of the Rio Negro. That makes all this hurry useless.”
“No, we still must keep ahead of Serbot,” Mr. Brewster insisted. “If Serbot has guessed where Nara is going, he will move up the Rio Del Muerte while we are coming down it.”
The bearers were waiting when they reached the campsite, and fell promptly into line. There was little difficulty in spurring them on. The mere mention that the Macus were behind them was enough. During the next few days, the bearers toiled steadily along the inland trail. Apparently, there was nothing that they feared more than the Macus.