This shows one way of providing a modesty piece that peeks out above the neckline of a bodice and presentable under-garments wherever a bodice or sleeves have openings.
1895-1900 French corset cover (Metropolitan Museum of Art - New
Madame J. H. (Johan Adolph) Rutherford, Corset, American
Place de Meir at Antwerp - Great Art Library - Paintings & Prints
photography – Art Blart _ art and cultural memory archive
Corset, European
Corset cover, American or European
Corset, French
Search The Collection - The Metropolitan Museum of Art
25 11 1895 hi-res stock photography and images - Alamy
LIVING THE AVANT-GARDE: THE TRITON COLLECTION FOUNDATION