By chance

I stumbled across the exit by chance.

[...] Yojo had told him two or three times over, and strongly insisted upon it everyway, that instead of our going together among the whaling-fleet in harbor, and in concert selecting our craft; instead of this, I say, Yojo earnestly enjoined that the selection of the ship should rest wholly with me, inasmuch as Yojo purposed befriending us; and, in order to do so, had already pitched upon a vessel, which, if left to myself, I, Ishmael, should infallibly light upon, for all the world as though it had turned out by chance; and in that vessel I must immediately ship myself, for the present irrespective of Queequeg.

Are you by chance looking for the exit?

If by chance you notice the fine, almost sweet maltiness of the aroma, and the brisk, dry, mineral quality of the flavors, even better.