Adopt an Artifact: Blueprint Machine

In the summer of 2024, Joan LaGrave and her daughter Elizabeth Albanese donated this blueprint machine to the National Building Museum. Recognizing its value to the history of architectural practice, Museum staff promptly placed it on display in Visible Vault: Open Collections Storage . Ever since, visitors have had fun guessing what exactly the machine is and are often surprised to learn about its original purpose.

Found in an abandoned warehouse in Mobile, Alabama, this immense glass tube is a large-scale Blueprint Machine. Made by the Chicago-based C.F. Pease Company in 1910, the machine was used to make cyanotype prints (also known as blueprints) from original drawings on tracing paper, parchment paper, or other types of translucent materials. Falling out of use by the mid-twentieth century, this hidden treasure remained in a storage unit for several decades before finding its final home at the Museum.

This specific model represents the oldest form of architectural copying technology. The cyanotype process, invented in 1842 as an early photographic method, became a standard technique for reproducing technical drawings well into the 1940s. It relies on photosensitive paper, typically treated with ammonium ferric citrate, that transforms from white to a deep blue when exposed to ultraviolet light. This effect gave rise to the term “blueprint.” To use the machine, drafts are first drawn with black ink on translucent tracing paper. These translucent drafts are then placed on top of the photosensitive ammonium-treated sheets. When using the machine, architects would clamp these two layers to the outside of the glass cylinder while shining a blacklight inside. The black ink of the overlaying drawing precisely blocks UV light from activating the sheet below, resulting in a high-fidelity, scale-accurate copy in white lines against the blue background.

This machine is only one of many types of blueprint machines, which range greatly in size and orientation. Although widely available at their height of popularity, these machines were almost completely replaced by diazonium or “whiteprint” copiers in the 1940s, which avoided the hazardous and pungent chemicals used in the blueprint process. These too were short-lived and were replaced in the 1970s by the xerographic photocopiers that are still standard today.

Help us preserve this history!

Click here to Adopt an Artifact and help protect this legacy.

The National Building Museum is home to the nation’s foremost archive of American architectural and design heritage. The Adopt an Artifact program allows you to directly support the proper care and preservation of objects with critical conservation needs, helping the Museum continue its mission to inspire curiosity about the world we design and build. To support this initiative, click here.