always slightly perplexing, as it clearly would have nothing to do with ‘jury-fixing’, e.g.
‘Death and the Judgment then? What? With all three masts making such an everlasting thundering against the side; and every sea breaking over us, fore and aft. Think of Death and the Judgment then? No! no time to think about Death then. Life was what Captain Ahab and I was thinking of; and how to save all hands—how to rig jury-masts—how to get into the nearest port; that was what I was thinking of.’
biblioklept.org
https://en.wikipedia.org/wiki/Jury_mast_knot