Next had come the excitement of packing, when it dawned on Biff that nearly all his birthday presents were clothes and equipment he could use on a tropical trip. Then Biff had flown to New York where Mr. Stannart had met him to put him on the plane for Brazil.
“Your father is bound on a highly important and secret mission for our company,” Mr. Stannart confided now. “He is going far up the Rio Negro, which joins the Amazon just below the city of Manaus. The party supposedly will be looking for sites for rubber plantations.”
Mr. Stannart paused, then said solemnly, “Your father will be looking for gold—a fabulous gold mine about which we have secret information. But here in New York,” he went on, “we have just discovered that there has been a leak in that information. We have learned that certain people would do anything to stop your father and get to the mine first. Even now, he may be in danger.”
“But Dad didn’t say anything about it—”
“Because he doesn’t know about it. He may change his mind about letting you accompany him after you give him this letter. It will tell him all he needs to know.”
Biff put the letter deep down into his coat pocket. Mr. Stannart nodded approvingly.
“Be careful what you say to strangers,” he warned Biff, “and above all, guard that letter!”
It was nearly time for the departure of Biff’s plane. Mr. Stannart explained that it would take him to Belem, the capital city of the Brazilian state of Para, not far from the mouth of the Amazon. There, Biff would change to a plane for Manaus, a thousand miles up the great river.
Mr. Stannart studied the other passengers who were waiting to board the plane. He said to Biff in parting, in a low but confident tone:
“You won’t have any trouble on this flight. But be careful after you leave Belem!”