Koehler Hold-to-Light Postcards
Joseph Koehler (J. Koehler, 150 Park Row, New York) published a series of chromolithograph postcards of American cities circa 1905–1910, all printed in Berlin, Germany. Each city view was issued as both a standard postcard and a hold-to-light (HTL) variant — a die-cut card with three layers: a chromolithograph top with tiny cut-outs, a sheet of colored tissue paper behind, and a backing card. When held to a light source, the cut-outs glow, making windows, streetlights, the moon, and water reflections appear illuminated. The standard and HTL versions look identical from the front; only the construction differs.
Koehler published HTL series for New York City (including a 12-card Coney Island set), Chicago, Boston, Philadelphia, Washington D.C., Buffalo, Atlantic City, Niagara Falls, and other cities. This registry covers the Boston, Philadelphia, and New York City series — approximately 12 cards each. Each city has its own page below.
Collection Overview
Koehler city-view postcards exist as both standard and hold-to-light versions. Since they look identical in scans, any Koehler card shown in the registry also exists as an HTL variant. Cards marked ★ In Collection link to detail pages; others are known to exist but are not yet in the collection.
About Hold-to-Light Postcards
| Feature | Details |
|---|---|
| Publisher | J. Koehler, New York–Berlin |
| Printer | Printed in Berlin, Germany |
| Era | c. 1905–1910 (undivided & divided back) |
| Technique | Die-cut chromolithograph, 3 layers with tissue paper |
| Size | 3½ × 5½ in. (8.9 × 14 cm) |
| Typical Price | $10–50 (common views); $50–175+ (rare views) |
