top stones are extraordinarily thick."

 

Bertie looked surprised. "Why, I should have thought the thicker they were

the more difficult to break up."

 

"Beyond a certain point that would be so. But suppose they are six inches

thick, you may take it for granted that underneath there will be rubble,

loose stuff, except where any chambers may be built. If we were to bore a

hole through this top layer the powder, instead of splitting the stones

up, would expend its force among the loose stuff beneath it; and besides,

instead of remaining in its place, it might get scattered, and we would

then get no explosion at all."

 

"Then we should only have to make the hole four inches deep, Harry?"

 

"As a result of which there would only be two inches of tamping over the

powder, and this would blow right out, as if from a little mortar, and

would have no effect whatever upon the stone. I have no doubt that we

shall find some way to get over these difficulties, but it is evident that

the work will not be all clear sailing."

 

"Of course we shall manage it somehow, Harry, even if we have to smash up

all the stones with the sledge-hammers Dias will bring us."

 

"Is breakfast nearly ready, senora? That swim in the sea has given us a

prodigious appetite. Did you enjoy it?"

 

Maria nodded.

 

"It is very nice, senor; but I should have liked it better if the water

had not been so blue. It seems so strange bathing in blue water."

 

"You will soon get accustomed to it," Bertie laughed. "There are no pools

except that one two miles up the valley. Besides, it is much nicer to have

a great bathing chamber all to yourself. Here comes Jose!"

 

"Well, Jose, are the mules all right?" he shouted.

 

"Yes, but I had difficulty in catching them. They had evidently been

frightened by something, and were three miles up the valley with their

coats all staring. It must have been either a puma or a jaguar. Of course

they must have got wind of him in time; but as, fortunately, they were not

tethered, they were able to get away from him."

 

"I should think he must be up somewhere among the bushes, Jose," Harry

said. "We had better go down tonight and see if he returns again. We shall

be losing some of the mules if we don't put a stop to his marauding

Besides, it will be very dangerous for you, Jose, cutting the wood up

there, if he is lurking somewhere. It is fortunate that you escaped