What is the poem To Jennie about by Mark Twain?

You're likely thinking of the poem "To My Old Sweetheart" by Mark Twain, not "To Jennie". This poem is often mistakenly attributed to "To Jennie" but there is no known poem of that name by Mark Twain.

"To My Old Sweetheart" is a lighthearted and humorous poem that reflects on the passing of time and the bittersweet memories of a long-ago love. It's a playful look at how love and life change over the years.

Here's a snippet of the poem:

> "I've got the same old heart, you see,

> That beats with just the same old beat

> I've got the same old love for thee

> But, ah! — it's so much out of date."

If you'd like to read the full poem, you can find it online or in many anthologies of Mark Twain's works.