Is it This one?
ODE TO THE FOUR LETTER WORD

Banish the use of the four-letter words
Whose meanings are never obscure
The Angles, the Saxons those hardy old birds
Were vulgar obscene and impure
But cherish the use of the weaselling phrase
That never quite says what you mean
You'd better be known for your hypocrite ways
Than as vulgar impure and obscene

When nature is calling, plain speaking is out
When the Ladies, God Bless'em are milling about
You may pee-wee, make water, or empty the glass
You can powder your nose, even Johnny may pass
Shake the dew off the Lily; see a man about a dog
When every ones soused, it's condensing the fog
But please to remember, if you would know bliss
That only in Shakespeare do characters piss

A woman has bosoms, a bust or a breast
Those lily-white swellings that bulge 'neath her vest
They are towers of Ivory, sheaves of new wheat
In a moment of passion, ripe apples to eat
You may speak of her nipples as fingers of fire
With hardly a question of raising her ire
But by Rabelaise's beard she will throw several fits
If you speak of them roundly as good honest tits

It's a cavern of Joy you are thinking of now
A warm tender field awaiting the plough
It's a quivering pigeon caressing your hand
Or the National Anthem-It makes us all stand
It's known among men as the centre of Love
The hope of the world or a velvety glove
But friend, heed this warning, beware of affront
Of aping the Saxon--- don't call it a c***

Tho' a Lady repels your advance, shell be kind
As long as you intimate what's on your mind
You may tell her your hungry; you need to be swung
You may ask her to see how your etchings are hung
Or mention the ashes that need to be hauled
Put the lid on her saucepan even "lay" is not too bald,
But the moment you're forthright, get ready to duck
For the girls isn't born yet who'll stand for "lets F***

So banish the words that Elizabeth used
When she was a Queen on the Throne
The modern maids' virtue is easily bruised
By the four-letter words all alone
Let your morals be clean as an Alderman's vest
If your language is always obscure
Today not the act but the word is the test
Of the vulgar, obscene and impure