“Hello! what can be keeping Hercus so long?” asked Robbie, when we had walked some distance.

I told him about the rat that the dog was after, and looked back for Willie.  Not seeing him, we concluded he had gone round by the top of the cliffs, and we continued our way a few yards further.  Then we heard Hercus calling after us in an excited way.

“Come back, lads, come back!” he shouted; and I looked at the sea line, fearing lest it was the rising tide that Hercus was warning us against.

“I’m not going back,” objected Tom.  “We’ve got time to get to the other side long before the water’s up.  Besides, I’m hungry.  I’m going home.”

“Tut, didn’t we wait for you while you skinned your seal?  Let’s go back,” I urged.  “Maybe Hercus is hurt.”

“Come away back, Tom,” added Rosson.

So we all returned to where Willie Hercus still remained, and wondered what he could mean by calling us back.

When we entered the chasm we were much surprised to find Hercus lying flat on the shingle, with his right arm deep in a hole he had dug, and the dog at his side, wagging her tail and uttering short barks of excitement.

“Good sakes!” exclaimed Robbie Rosson.  “What’s wrong with the lad?”

Much relieved we were to hear Hercus speak.  I confess I had felt certain some harm had happened to him.

“Come away,” he said, in a tone which was far from being a cry of pain.  “Come away, lads, and give us a hand here.  There’s better gear than rats in this hole, I’m thinking.”

And, so saying, he rose to his knees and held out to us a heavy and black piece of metal, which at first I took to be an iron bolt.

“Well, what is it?” I asked, taking the thing in my hand and examining it.

“What is it?” said Hercus.  “Can you not see, lad?  Why, it’s silver!”

Chapter VII.  What The Shingle Revealed.

Now the explanation of Willie’s curious discovery, as we afterwards fully learned, was this:  When I took up the dead falcon, Hercus, intent upon witnessing Selta’s skill at ratting, stood beside the dog as she scraped with her forefeet the shingle from the crevice through which the rat had escaped.  Disappointed at losing her prize, the terrier dug and dug away at the shingle and moist sand, scattering it behind her, and burying her nose deep down.  Then a strange, grim object was unearthed.  In the midst of the stones, Hercus, to his horror, saw lying there a ghastly human skull, with the great cavities where the eyes had been, staring at him.  Hesitating at the sight of this frightful spectacle, he at last mustered courage to take the thing in his hand.  He was in the act of examining it, when, from one of the hollow eye sockets, out jumped the fugitive rat.  Had the jaws of the skull moved in speech, Willie could not have been more terrified than he was by seeing the rat spring from its strange hiding place.