Classic Poem

I have a secret to myself,
That no one else can see.
I hum it over to myself,
And no one hears but me.
—Something You don't know!
I knew long ago.—
And the more I never tell you it,
The more it gets to be.

It makes me feel as purry
As the Kitten on your knee.
It makes me feel as round and warm
As the Sparrow on that tree;
It makes me puff my feathers out
The way he puffs out his.—
And if you think I haven't one,
I'll tell you what it Is,