to fix on

Webster's Dictionary (GCIDE)

1.To become fixed; to settle or remain permanently; to cease from wandering; to rest. [1913 Webster]

Your kindness banishes your fear, Resolved to fix forever here.— Waller.[1913 Webster]

2.To become firm, so as to resist volatilization; to cease to flow or be fluid; to congeal; to become hard and malleable, as a metallic substance. --Bacon. [1913 Webster]

To fix on, to settle the opinion or resolution about; to determine regarding; as, the contracting parties have fixed on certain leading points. [1913 Webster]