unweariable

Fjalar's short legs had to swing faster, but he seemed unweariable.

Dusty of face, with frugal refreshment, they plod onwards; unweariable, not to be turned aside.

So it is in rugged crises, in unweariable endurance, and in aims which put sympathy out of question, that the angel is shown.

But he leaped across the plashy places, thrust himself through the clinging underbrush, climbed the ascent, plunged into the hollow, and overcame, in short, all the difficulties of the track, with an unweariable activity that astonished him.

When I dwell upon some one thing, he must bear in mind it was only one of a score; that the unweariable brain was teeming at the very time with other thoughts; that the good heart had left no kind duty forgotten.