Looking For A Poem

I am looking for a poem that I heard once ages ago and parts of it stuck with me, the poem is about someone or something called Adelaide and I have since adopted a cat with the same name which triggered me off to search for the poem.
The only parts I know are; -

Adelaide was quite dismayed,
The more she ate, the less she weighed,
The less she weighed, the more she ate,
And addled Adelaide lost weight.

She stuffed herself with meat and cheese,
Potatoes, pumpkins, pies and peas,
But standing on the scales she found,
That she had lost at least a pound.

I really hope that someone can help me on this one as it's driving me nuts! !