But the look in Jasper’s eyes was very beseeching, and he tried to push his head in so that he might lay his nose against Ralph’s breast.

The boy put his arms about the beast’s neck.

“I can’t do it, Jasper,” he repeated, sobbing.  “Don’t you see I can’t?  I wisht I could, oh, I wisht I could!”

The animal drew his head back.  His position was uncomfortable, and it choked him to stretch his neck out that way.

Ralph knew that he must proceed with the building of his wall.  One after another he laid up the pieces of slate and coal, chinking in the crevices with dirt, keeping his head as much as possible out of the foul current, stopping often to rest, talking affectionately to Jasper, and trying, in a childish way, to console him.

At last his work was nearly completed, but the gruff sounds of distress from the frightened mule had ceased.  Ralph held his lamp up out of the current, so that the light would fall through the little opening, and looked in.

Jasper lay there on his side, his head resting on the coal bottom, a long, convulsive respiration at intervals the only movement of his body.  He was unconscious, and dying.  The boy drew back with tears in his eyes and with sorrow at his heart.  The beast had been his friend and companion, not only in his daily toil, but here also, in the loneliness and peril of the poisoned mine.  For the time being, he forgot his own misfortunes in his sympathy for Jasper.  He put his face once more to the opening.

“Good-by, Jasper!” he said, “good-by, old fellow!  I couldn’t help it, you know, an’—­an’ it won’t hurt you any more—­good-by!”

He drew back his head, put the few remaining stones in place, chinked the crevices with dirt and culm, and then, trembling and faint, he fell to the floor of the old mine, and lay there, panting and exhausted, for a long time in silent thought.

But it was not of himself he was thinking; it was of poor old Jasper, dying on the other side of the black wall, deserted, barred out, alone.

Finally it occurred to him that he should go to some other place in the mine.  The poisonous gases must still be entering through the crevices of his imperfectly built and rudely plastered wall, and it would be wise for him to get farther away.  His oil had nearly burned out again, and he refilled his lamp from the can.  Then he arose and went down the chamber.

It was a very long chamber.  When he reached the foot of it he found the entrances into the heading walled up, and he turned and went along the air-way for a little distance, and then sat down to rest.

For the first time he noticed that he had cut his hands badly, on the sharp pieces of coal he had been handling, and he felt that there was a bruise on his side, doubtless made when he fell through the opening.

Hitherto he had not had a clear idea as to the course he should pursue when he should have obtained entrance into the old mine.  His principal object had been to get into pure air.