Blueprint
Blueprints are reproductions of architectural or engineering design plans, historically characterized by a blue color that emerged from a photographic copying method developed in the 19th century. The term "blueprint" originated from the cyanotype process discovered by Sir John Herschel in 1842, which allowed for the production of blue images on light-sensitive paper or cloth. This method revolutionized how architects and engineers reproduced their designs, enabling them to create detailed plans more efficiently and cost-effectively than manual tracing.
Throughout history, architectural drawings have played a crucial role in design, with skilled draftsmen meticulously copying original designs, dating back to significant examples like the Plan of St. Gall from the 9th century. While blueprints typically used linen or vellum and dominated construction practices for decades, the introduction of diazo prints in the 1940s shifted the medium to white paper with blue lines. Today, advancements in technology, particularly Computer-Aided Design (CAD), have largely replaced traditional blueprinting methods. However, the term remains widely used to denote any detailed design plan in construction and engineering, regardless of the actual coloration of the drawings.
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Blueprint
A blueprint is a reproduction of an architectural or engineering design plan or technical drawing. Using a method first developed in the nineteenth century, blueprints got their name from the blue color that would form on photosensitive paper or cloth used during copying. While technological advancements have made the blueprint process obsolete, the term still describes any design plan used in construction or engineering.
The Origins of Blueprints
Builders and engineers have been using architectural drawings to design structures for hundreds of years. One of the oldest surviving examples is the Plan of St. Gall, an outline for a ninth-century monastery that was never built. Through the centuries, architects and inventors would transfer their visions onto paper, paying meticulous attention to proper scale and perspective. Skilled draftsmen were used to make additional versions of these plans by painstakingly copying the original.
In 1842, an English chemist, astronomer, and photographer named Sir John Herschel discovered a process called cyanotype after a series of experiments. The method involved taking an image drawn on semitransparent paper and laying it on a sheet of paper or cloth coated with a photosensitive mixture of chemicals, including potassium ferricyanide and ferric ammonium citrate. The drawing was then exposed to light, and over time, the background or exposed sections of the drawing turned blue, while the darker lines blocked the paper from the light and remained white.
The process was first used to reproduce images of leaves and plants for botanical illustrations and was also popular among amateur photographers. Architects soon took notice of the method and began using it to reproduce copies of their design plans. By the end of the nineteenth century, architects and engineers could produce detailed "blue prints" of their plans at a fraction of the cost and in considerably less time than tracing by hand. These blueprints were usually made on linen or vellum—a form of parchment made from animal skin—and remained the standard in construction and engineering projects for decades.
In the 1940s, a process known as diazo print became popular. A diazo print, also known as a whiteprint, used a chemical process similar to cyanotype, but produced blue lines on white paper. By the late twentieth century, advances in computer technology began to make the need for copying technical drawings obsolete. Architects and engineers in the twenty-first century use a system called Computer-Aided Design (CAD) to create a design plan and simply print it out or transfer it digitally via computer. Despite the fact that blueprints are no longer blue, the term is still used to describe technical drawings used for engineering or construction projects, and as a generic reference to any detailed plan of action.
Bibliography
"Blueprints, Then and Now." New-York Historical Society Museum & Library. New-York Historical Society. 24 Jan. 2012. Web. 17 Dec. 2015. http://blog.nyhistory.org/blueprints-then-and-now/
Cooper, Emily. "The History of Blueprints." PlanGrid. PlanGrid. 1 July 2013. Web. 17 Dec. 2015. http://blog.plangrid.com/the-history-of-blueprints
Kocha. "History of the Blueprint." Avalon Document Services. Avalon Document Services. 14 July 2014. Web. 17 Dec. 2015. http://www.teamavalon.com/history-of-the-blueprint/
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