"Only say you love Mr Callaghan ..."

Would that be from words put to Barney Brallaghan then?

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Melodist, and Mirthful Olio;: An Elegant Collection of the Most Popular Songs, Recitations, Glees, Duets, &c. &c. Intermixed with Many Originals, and Some of the Most Favorite of Dibdin, Moncrieff, &c. Embellished with Humouous Wood Engravings.. (Google eBook)