Here's the midi link: http://www.contemplator.com/england/gogetax.htm

Here is the version I learned:

Peeping through the knothole in father's wooden leg
who'll wind the clock when I am gone?
Go get the meat ax, there's a fly on baby's bean
a boy's best friend is his mother.

Peepin' through the knot-hole of grandpa's wooden leg,
Why do they build the shore so near the ocean?
Who cut the sleeves out of dear old daddy's vest,
And dug up Fido's bones to build the sewer?

Here is the HARVARD VERSION of the first verse:

Peering through the aperture in father's artificial appendage
who'll tighten the chronometer when I cross the bar?
go procure the viand dissector, there's an insect on baby's cerebellum
one of the greatest sociological factors of the development of the male of the species Homo Sapiens is his immediate maternal ancestor.