Embossed, H.L.P M, upper cover. Incised "Patented 1909-12-20" below red lenses. Made by Hiram Piper, Montreal. Circa 1910. Each lamp features one panel that slides up to reveal their original burner and fount assemblies. These "caboose" or "marker" lamps were used to mark the rear of a train with red lights if moving and green lights if passable. 15.5" x 9" x 9". Lenses are free of chips, cracks, exhibit just light scuffs. Older repaints. Each retains original mounting bracket. Est. $200-400. CODE-RAIL. CODE-HISO