There are many variants of the tune, but that one is a Fieldtown version popularised by 'Morris On', and mostly performed as a solo Jig... here's the ABC:

X: 1
T:Princess Royal, Morris On
M:4/4
L:1/8
A:Fieldtown
P:AAB(CB)2
K:G
P:A
dc|B2A2 G2dc|B2A2 G2d2 |e2c2 cdec|d2c2 B3d|
c2B2 A2G2|FGAF D2dc|BABG A2F2|G6 ||!
P:B
d2|e3d e2d2|e2f2 g3f|g2f2e2d2|BAG2 A2BA|G2G2 A4|BAG2g3f|g2d2 e4|d2B2c3d|
c2B2A2G2|FGAF D2dc|B2AG A2F2|G4 ||!
P:C
d2c2|B4A4| G4d2c2|B4A4| G4d4 |e4c4| c2d2e2c2|d4c4| (B6B)d|
c2B2 A2G2|FGAF D2dc|BABG A2F2|G4 G2 ||