Mbo and Bagpuss, that is Sandie Toy and the words are in the DT. My Mom, brother and I learned it from my grandmother and sing it too, with the addition of the following verses

I came to a river
I couldn't get across
Payed 2 shillings for an old blind horse
I jumped on his back
His bones gave a crack
I played on the fiddle till the boat came back

The boat came back
We all jumped in
The boat capsized and we all fell in
Crack goes one
Crack goes two
Crack goes my hand over you.