"They told me you had been to her..." is a poem by Lewis Carroll appearing in Chapter 12, "Alice's Evidence", of Alice's Adventures in Wonderland. It was recited as evidence by the White Rabbit at the Knave's trial for stealing the tarts. The poem is a revised version of a nonsense poem by Carrol printed in The Comic Times in 1855.
The poem is found written on a piece of paper presented as the last piece of evidence by the White Rabbit at the Knave's trial. It is alleged to be written by the Knave, but is not addressed to anybody. The King and Queen of Hearts say this establishes the Knave's guilt, something that Alice contests. At this the King orders the White Rabbit to read the poem, upon conclusion of which Alice says that she doesn't believe there's any meaning in it, while the King still tries to make sense of the poem. Soon afterwards, Alice's dream ends as she is woken up by her sister.
They told me you had been to her,
And mentioned me to him:
She gave me a good character,
But said I could not swim.
He sent them word I had not gone
(We know it to be true):
If she should push the matter on,
What would become of you?
I gave her one, they gave him two,
You gave us three or more;
They all returned from him to you,
Though they were mine before.
If I or she should chance to be
Involved in this affair,
He trusts to you to set them free,
Exactly as we were.
My notion was that you had been
(Before she had this fit)
An obstacle that came between
Him, and ourselves, and it,
Don't let him know she liked them best,
For this must ever be
A secret, kept from all the rest,
Between yourself and me.