Most of the 18th century material is divided into two sections: the music published in Baltimore and that published in New York, Philadelphia and Boston. Oscar Sonneck and William Upton, the bibliographers of early American secular music, list a number of items in the collection that are unique; a number of others, unknown to them, have been added since the publication of their bibliography in 1945. Of major interest are compositions by recognized American composers: Benjamin Carr, Alexander Reinagle and Raynor Taylor. A number of their songs appear in Young's Vocal Miscellany (1793-95) and in Carr's Musical Journal. An instrumental work is A New Assistant for the Piano Forte or Harpsichord, published by Carr in 1796.

Many English composers are represented in this section, as well as songs sung by popular English singers of the period.

A few 18th century items may be found elsewhere in the collection, such as the "New Federal Song" in the Patriotic section, songs honoring Washington or Adams in the Presidents section, and even a Masonic number included in the folio under Fraternal Orders.