“I didn’t tell you fellows much about this before,” he said. “I wanted to see your eyes pop out. Thought you were going to run into something wild and savage, didn’t you? Well, this is the most beautiful residential city in South America, and one of the most beautiful in the world. Isn’t it, father?” he appealed.

Mr. Hampton nodded.

“Santiago and Rio de Janeiro hold the palm in that respect,” he said. “Rio, however, because of its wonderful harbor and mountainous surroundings is, in my eyes at least, a bit the more beautiful. Yet, as you can see, Santiago’s natural beauties would be hard to surpass. However, here we are at Senor de Avilar’s home. Let us hope the accident to his son has not been serious. In that case, we cannot stay, as we would embarrass the family, but will go to a hotel.”

They had expected Senor de Avilar to greet them in person on arrival, but had been told by the driver that at the last moment the latter had been called to a point outside the city where his son, Ferdinand, had been injured when thrown from a runaway horse.

Fortunately, it developed, the accident had not proven serious. The young son of the house, a youth of their own age, had sustained a fractured wrist, but otherwise had escaped unharmed. He was a charming boy with a fairly good command of English, and he and the boys became warm friends during the ensuing week.

As Jack, owing to his previous visit to South America, on which occasion he had learned the language, could speak and read Spanish fluently, and as he had imparted considerable knowledge of the language to Frank and Bob, the four got along famously. Horseback rides about the city and its environs were of daily occurrence, young de Avilar managing his mount in superb fashion despite the injured wrist.

During the week, the boys saw little of Mr. Hampton and Senor de Avilar. The two older men were closeted in long conferences with others every day. For a number of reasons, the boys were curious to know the nature of these conferences.

In the first place, at the beginning of their summer vacation from Yale, Mr. Hampton, a consulting engineer of international reputation, had called Jack into his study in their home on Long Island, adjoining the Temple home at which Frank, an orphan, resided, and had smiled a little as he said:

“Well, Jack, how would you and the boys like to go with me hunting treasure this summer?”

Hunt treasure?