Evidently not a particle of gas was escaping through the rock.
"Nothing!" cried Ford, clenching his fist with a gesture rather of anger than disappointment.
A cry escaped Harry.
"What's the matter ?" asked Starr quickly.
"Someone has stopped up the cracks in the schist!" "Is that true ?" exclaimed the old miner.
"Look, father!" Harry was not mistaken.

The obstruction of the fissures was clearly visible by the light of the lamp.

It had been recently done with lime, leaving on the rock a long whitish mark, badly concealed with coal dust.
"It's he!" exclaimed Harry.

"It can only be he!" "He ?" repeated James Starr in amazement.
"Yes!" returned the young man, "that mysterious being who haunts our domain, for whom I have watched a hundred times without being able to get at him--the author, we may now be certain, of that letter which was intended to hinder you from coming to see my father, Mr.Starr, and who finally threw that stone at us in the gallery of the Yarrow shaft! Ah! there's no doubt about it; there is a man's hand in all that!" Harry spoke with such energy that conviction came instantly and fully to the engineer's mind.

As to the old overman, he was already convinced.
Besides, there they were in the presence of an undeniable fact--the stopping-up of cracks through which gas had escaped freely the night before.
"Take your pick, Harry," cried Ford; "mount on my shoulders, my lad! I am still strong enough to bear you!" The young man understood in an instant.