Products: buttons, beveled plate and mirror glass, cullet ("once popular as simulated coal for fireplace grates"), "cathedral and rough-rolled glass, Flemish, English crown bullion and broad reeded glass, rippled, hammered and many other types of church and office glass", dalles de verre, glass gems, jet and jade, simulated pearls, hat-pins, mosaic tesserae (Murano), bathroom windows, colored sheet glass (signs), glass for light fixtures and X-ray boxes, lampshades, glass for lighthouses (and funeral parlors), electric meter covers, beads (Murano, Czech), magnifying lenses, signal glass (RR), dolls eyes, fish and moose eyes, typewriter keys, elevator lights, and glass for furniture and architecture, including, of course, vault lights. This is just a sampling— they dealt in all things glass.

Buttons were an early product— Leo began making them at 338 Pearl St. before 1880 (some say mid 1870s)— and it's buttons that Popper is mostly known for today. Specifically, glass buttons in many shapes with an endless variety of rainbow metallic inclusions. They're favored by button collectors, who call them, not surprisingly, "Poppers".

The reason Popper is included in this site is vault lights. When they closed in 1971, Whittemore-Durgin bought their stock on hand, which included barrels of baby (~2") single-pendant vault lights and plain flat bulls-eye lenses. A scale cut of the pendent lens appears in Tice & Jacobs' Illustrated Catalogue of Vault Lights (page 38), so presumably this article was made or supplied for T&J. Some of the lenses are embossed "PAT AUG 30 1880", which is not a Tuesday; this is an engrave-o and should read "AUG 31", the date of Jacobs' patent. The bulls-eyes are generic, with no markings, and could have been used by anyone.

Interview: "...with Emil L. Popper, 81, proprietor of the firm of Leo Popper & Sons, dealers in fancy & colored glass Received reported in his office on Franklin St., in a dimly lit, weakly heated room. He said that his father, Leo, brought here from Prague as a boy, founded the business in 1880. Firm handles imported & domestic glass which it sell largely to firms that install stained-glass windows in churches. Its glass is also used in lighting fixtures, sign fish lures, eyes for stuffed animals & push buttons for elevators. Mr. Popper is more interested insoluble geometry than in the business. He showed a letter Albert Einstein wrote him in '44, in answer to one from him. Met Popper's son, Edwin L., who is forty. He said the business is inefficient in every way but they like it." —The New Yorker, February 3, 1951 P. 25