The collection of popular instrumental sheet music is an artificial collection of sheet music primarily intended for solo piano. A legacy of former practice based on patron expectations, this piano sheet music (that is, published music of about 2-8 pages) was not cataloged but placed into one of four categories: General, Marches, Rags, Shows.
This collection includes only sheet music that was "uncataloged." Cataloged instrumental sheet music can be found in the online catalog as well as the Dictionary Catalog of the Music Collection.