2 Verbs to Use for the Word hardiness

In a former letter, wherein I gave you my motives for making this attempt, I mentioned their extreme hardiness; of this I had now additional proofs: these birds were in a coop on the deck, and I expected every sea we shipped over our quarter during the first gale, they certainly would be drowned; but was agreeably surprised, when the gale was over, to find them very little the worse for their severe ducking.

Trials for the special purpose of testing the hardiness of the more tender kinds have been instituted and carried out in several favoured parts of England and Ireland.

2 Verbs to Use for the Word  hardiness