This post is part of a monthly series that explores the historical applications of building materials and systems through resources from the Building Technology Heritage Library (BTHL), an online collection of AEC catalogs, brochures, trade publications, and more. The BTHL is a project of the Association for Preservation Technology, an international building preservation organization.

Signage has long been used to indicate places of business, worship, hospitality, and more. In the 19th and 20th century, façade and building elements took on new life with the electrification of major metropolises, making places like New York’s Times Square and the Las Vegas Strip flashing beacons of tourism and spectacle. Eventually, the neon tube lamp and other light sources gained popularity, further illuninating cityscapes around the globe.

Here, the BTHL chronicles the evolving design and technology of architectural signage from the 20th century.

E.T. Barnum, Manufacturer of Bank Railings, Iron Fencing, Roof Cresting, Wire and Iron Work, Detroit, 1878
This is one of the oldest documents in the BTHL, advertising a metal and mesh signage system. Designed to be fixed to the outside of a commercial building, the metal frames were also available in rooftop mounting options.

Illustrated Catalogue and Price List of the Benfield & Milne Mfg. Co., Newark, N.J., c. 1900
This catalog of sign letters and backgrounds offers components cast in brass, bronze, and aluminum as well as wood letters and porcelain enamel signs. “Intricate designs and special ideas of architects and others carried out with the greatest care and attention to detail,” the publication promises.

Electric Signs, the Metropolitan Engineering Co., Brooklyn, N.Y., 1906
“We have endeavored in the catalog to represent as much as possible the various types of electric signs which are popular today,” the Metropolitan Engineering Co. writes. The company offered various sign types such as attraction letter, raised letter, and panels signage, as well as the “newest electric sign letter on the market”—a pressed steel letter with a porcelain enamel color advertised as “absolutely imperishable.”

Sign Lighting with Edison Mazda Lamps, General Electric Co., Schenectady, N.Y., 1915
This catalog from General Electric features the then-latest sign lamps from across the country, which were advertised as an improvement over the previous carbon filament lamps.

Sign-Tific Advertising, A & W Electric Sign Co., Cleveland, 1915
This illustrated catalog offers examples of electric signage in various sizes and styles. “The cumulative effect of ‘Sign-tific Advertising’ is not gained by size nor any number of lamps,” the manufacturer writes, “but by character, distinctive appearance, original application of ideas, and its harmonious relation to the business it represents.”

Pattern Letters & Figures Catalogue, H.W. Knight & Son, Seneca Falls, N.Y., 1927
This catalog features an extensive library of fonts and technical guidance for letter spacing of architectural and industrial signage.

Signs and Sign Letters, George Steere & Sons, Chicago, 1929
George Steere & Sons sold stock and custom signs as well as individual sign letters in bronze, brass, and vitreous enamel. The company also offered a complete line of window sign letters and graphic emblems.

Decorative Signs by Todhunter, New York, 1930
Todhunter specialized in hand wrought metal decorative signs, with an emphasis on silhouette art.

Neon Sign Machinery, Eisler Engineering Co., Newark, N.J., 1928
The neon sign made its debut in France and came to America in the 1920s. Eisler sold the various machinery and components necessary for glass neon sign bulbs and tubes.

Brilliant Neon Signs That Attract, Brilliant Neon Limited, London, 1940
Billing itself as the “largest sign works in the empire,” Brilliant Neon Limited sold multicolored neon signage with free colored renderings ahead of purchase. In this catalog, the company highlights its products throughout the U.K.

Wood Letters, Spanjer Brothers, Chicago, 1957
For permanent and temporary installations, Spanier Brothers promoted the use of wood signage, which remained popular despite the emergence of electric signs.

White Way Electrical Advertising Displays, White Way Electric Sign and Maintenance Co., Chicago, 1963
This catalog acts as the de facto monograph of architectural signage of the Chicago area.