"I Saw Three Ships"
Sung by The Choir of Clare College, Cambridge.
This is a lovely arrangement of the traditional carol, which dates back to 17th Century England (most likely Derbyshire-- where my father was born. Not in the 17th Century, however... He would want me to point that out).
There are many versions of the carol, and it is often found in books of nursery rhymes. The lyrics used here can be found in "Christmas Carols, Ancient and Modern", by William Sandys, published in 1833.