Subject: Mathematical instruments

This trade card advertises Janentzky & Co., purveyors of mathematical instruments and drawing supplies. The front of the card (Image 1) showcases an elegant design, possibly incorporating illustrations of some of their products. The text clearly displays the business' name and address: 1125 Chestnut St., Philadelphia. The back of the card (Image 2) mentions a "Centennial Exhibit," indicating the card likely dates to the 1876 Philadelphia Centennial Exposition. The back may contain additional details related to their participation in the exposition.

Trade card for Sussfeld, Lorsch & Co., importers of optical and mathematical instruments, watchmakers' tools, and materials. The card lists their New York City address as 13 Maiden Lane and their Paris address as 27 Rue de Paradis Poissonniere. It also notes their participation in a Centennial Exhibition. Undated, but likely from around 1876.