Definition of "governail"

We immediately threw out all the little things we had with us, ſuch as biſcuits, apples, &c. and after that one of our oars or wings; but ſtill deſcending, we caſt away the other wing, and then the governail ; having likewiſe had the precaution, for fear of accidents, while the Balloon was filling, partly to looſen and make it go eaſy, I now ſucceeded in attempting to reach without the Car, and unſcrewing the moulinet, with all its apparatus; I likewiſe caſt that into the ſea.

1786, John Jeffries, Jean-Pierre Blanchard, A narrative of the two aerial Voyages of Dr. J. with Mons. Blanchard: with meteorological observations and remarks.‎, page 45

That he has contrived a “ self-acting governail, which has the peculiar power of directing the course of the vessel, entirely independent of the action of the helm, and which is positively called into operation by the very presence of danger."

1834, The Printing Machine: Or Companion to the Library, and Register of Progressive Knowledge, Volumes 1-3‎, London: William Clover, page 61

But this whole arsenal of methods remained only a metaphor when it came to the art of governing men politically. What does the helmsman with his governail have to teach those who govern?

1995, Michel Serres, The Natural Contract‎, University of Michigan Press, page 43