This is a transcription of the ouverture to the opera Agrippina as printed by Walsh in 1712. Händel's opera Agrippina premiered in 1709, but the source used for this transcription is a facsimile of the 1712 Walsh print, specifying it as the ouverture to the opera Antiochus by Francesco Gasparini.
I have always tried to be as close to the original as possible. Editorial changes have been put above the staffs, or within parenthesis. Slashed figures in the continuo have been replaced with their flat/natural or sharp equivalents. All accidentals and clefs have been converted to modern standard.