They were allowed, on my representation, to rest from their arduous labours, and soon afterwards—as if their sole principle of life had been zeal for their country’s service—as I verily believe it was—withdrew to a better world.
There are no more uses of "arduous" in the book.
Show samples from other sources
At last, they won their long and arduous fight for independence.
She undertook the arduous work of caring for twins.