"Portsmouth" is a tune in Playford's Dancing Master, 1651. It has words, but I don't know them [tune in solfa is approximately: (4/4)s,/d- r mrdt,/ l,- l-/ s m fmrd/ r-- s,/ d- r mrdt,/ l,- l-/ m s fmrm/ d etc.] The "Princess Royal" is by Carolan, the Irish harper, and is probably used by VW on the basis of the name being borne by a ship in the Royal Navy. It turns up in the Scottish Country Dance Society books as a 28-bar reel.