I've found the following lyrics from this site. These may not be old enough, though.

Row, row, row your boat
Gently down the stream
Merrily, merrily, merrily, merrily
Life is but a dream

Dance, dance, dance your dolly
Gently down the stream
Merrily, merrily, merrily, merrily
Life is but a dream

Gallop, gallopy, gallop your horse
Down beside the stream
Merrily, merrily, merrily, merrily
Life is but a dream

Roll, roll, roll your hoop
Wobbly by the stream
Merrily, merrily, merrily, merrily
Life is but a dream

Bounce, bounce, bounce your ball
Down beside the stream
Merrily, merrily, merrily, merrily
Life is but a dream

~Masato