Let us rather
Hold fast the mortal sword; and, like good men,
Bestride our downfal birthdoom.—]
He who can discover what is meant by him that earnestly exhorts him to bestride his downfal birth-doom, is at liberty to adhere to the present text; but it is probable that Shakespeare wrote,
—like good men,
Bestride our downfaln birthdom—
The allusion is to a man from whom something valuable is about to be taken by violence, and who, that he may defend it without incombrance, lays it on the ground, and stands over it with his weapon in his hand. Our birthdom, or birthright, says he, lies on the ground, let us, like men who are to fight for what is dearest to them, not abandon it, but stand over it and defend it. This is a strong picture of obstinate resolution. So Falstaff says to Hal.
When I am down, if thou wilt bestride me, so.
Birthdom for birthright is formed by the same analogy with masterdom in this play, signifying the privileges or rights of a master.
Perhaps it might be birth-dame for mother; let us stand over our mother that lies bleeding on the ground.