WEBVTT - Why Are Blueprints Blue? 0:00:01.920 --> 0:00:07.160 Welcome to brain Stuff production of iHeart Radio. Hey brain Stuff, 0:00:07.200 --> 0:00:10.880 Lauren vocal bomb here. If you have a blueprint for success, 0:00:11.000 --> 0:00:13.159 you're not alone, at least when it comes to the 0:00:13.200 --> 0:00:16.079 blueprint part. The word blueprint has become part of a 0:00:16.079 --> 0:00:19.919 global lexicon used to symbolize a plan, strategy, or framework. 0:00:20.320 --> 0:00:23.600 But what is a blueprint really? At its most basic, 0:00:23.640 --> 0:00:26.640 a blueprint is a reproduction of an image that already exists. 0:00:27.080 --> 0:00:30.640 Engineers or architects use these large format prints to illustrate 0:00:30.680 --> 0:00:33.720 project plans, using white lines and text on a backdrop 0:00:33.800 --> 0:00:36.400 of blue. And it's not just because they happen to 0:00:36.440 --> 0:00:39.839 like the color. A blueprint signature hue is tied to 0:00:39.880 --> 0:00:44.000 a chemical process. In eighteen forty two, an English photographer, chemist, 0:00:44.040 --> 0:00:47.879 and astronomer named John Herschel discovered the combining ferric ammonium 0:00:47.920 --> 0:00:51.599 citrate and potassium fair cyanide created a chemical reaction and 0:00:51.680 --> 0:00:56.360 a compound called blue ferric fair sydanide or Prussian blue. 0:00:57.360 --> 0:01:00.600 This photosensitive solution could be used to reproduces documents in 0:01:00.640 --> 0:01:03.680 a process similar to developing a photograph from a negative. 0:01:05.200 --> 0:01:08.920 The process, called cyana type, was adopted by early photographers 0:01:08.959 --> 0:01:11.920 and led to the first book illustrated by photography, and 0:01:11.959 --> 0:01:15.800 then became the darling of architects and engineers. Here's how 0:01:15.840 --> 0:01:19.200 it works. First, you create a drawing, then transfer it 0:01:19.319 --> 0:01:22.280 to vellum paper or tracing cloth, both of which are 0:01:22.319 --> 0:01:25.399 so thin that light can pass through them. Then you 0:01:25.440 --> 0:01:28.759 saturate a piece of regular paper with an ammonium potassium 0:01:28.800 --> 0:01:32.560 mixture and let it dry. Place the transparent vellum or 0:01:32.600 --> 0:01:35.000 tracing cloth with the drawing atop the paper coated in 0:01:35.040 --> 0:01:38.279 the chemical solution, Shine a bright light down through the drawing, 0:01:38.560 --> 0:01:41.479 and wait for the chemical reaction to take place. Within 0:01:41.480 --> 0:01:43.800 a matter of minutes, the chemical coated paper will be 0:01:43.840 --> 0:01:48.480 transformed into blue ferric fairr cyanide, with one important exception, 0:01:49.640 --> 0:01:52.560 wherever the light can't shine through the top paper because 0:01:52.600 --> 0:01:55.400 of the lines from the drawing, the blue printing paper 0:01:55.480 --> 0:01:59.000 remains white. After rinsing the paper in cold water to 0:01:59.080 --> 0:02:01.680 halt the chemical action and allowing the paper to dry 0:02:01.720 --> 0:02:04.680 in the dark, you're left with a nearly identical duplicate 0:02:04.680 --> 0:02:07.560 of the original drawing, just the lines are white and 0:02:07.600 --> 0:02:10.359 the background is dark, where the lines were originally dark 0:02:10.360 --> 0:02:14.600 and the background was light. Although this process requires several steps, 0:02:14.720 --> 0:02:16.919 it became a big hit with the pre computer crowd 0:02:16.919 --> 0:02:19.240 of the nineteen and twenty centuries, as it was still 0:02:19.280 --> 0:02:22.400 faster and cheaper than creating large scale drawings by hand. 0:02:23.280 --> 0:02:25.600 The story of the creation of Prussian blue has all 0:02:25.639 --> 0:02:28.840 the elements of a dark fairy tale. In seventeen o four, 0:02:28.880 --> 0:02:32.600 an alchemist and a dye maker shared a laboratory in Berlin, Germany. 0:02:32.840 --> 0:02:36.840 The former, Johann Konrad Dipple, sought to create a universal remedy, 0:02:37.160 --> 0:02:40.519 one that treated everything from animal mange to human epilepsy 0:02:40.639 --> 0:02:43.880 by boiling hoofs, horns, and leather into a smelly elixir. 0:02:44.600 --> 0:02:47.160 The ladder, a fellow named Teese Box made batches of 0:02:47.240 --> 0:02:51.520 vibrant dyes. One day, as these, Box simmered insects, alum, 0:02:51.720 --> 0:02:54.560 iron and sulfate to create a deep red, he borrowed 0:02:54.600 --> 0:02:56.799 some potash to the alchemist and added it to his 0:02:56.919 --> 0:03:00.960 viscous mixture. This horrible brew created a blue as deep 0:03:01.000 --> 0:03:05.399 as the night sky. After retracing the steps in the process, 0:03:05.720 --> 0:03:09.400 Dipple realized the potash contained ox blood that, when mixed 0:03:09.400 --> 0:03:12.360 with iron sulfate, caused a chemical reaction and turned a 0:03:12.400 --> 0:03:15.600 brilliant shade of blue. Unlike other blue dyes that were 0:03:15.639 --> 0:03:19.079 difficult to make and easily faded. This blue remained vivid, 0:03:19.680 --> 0:03:22.480 and it was inexpensive. Other blue dyes of the time 0:03:22.520 --> 0:03:26.160 required ingredients like lapis lazili, which at the time cost 0:03:26.240 --> 0:03:30.880 more than gold. Initially, Dipple called the color Berlin blue 0:03:30.919 --> 0:03:33.680 as a nod to his city of residents. Later it 0:03:33.720 --> 0:03:35.800 was called Prussian blue because it was used to dye 0:03:35.840 --> 0:03:39.360 uniform fabric for the Prussian Army. The color became both 0:03:39.400 --> 0:03:42.280 the symbol of aggression and a term of endearment because 0:03:42.280 --> 0:03:45.720 of the army's fierce battles and serendipitous interventions and conflicts 0:03:45.760 --> 0:03:49.720 like the Battle of Waterloo. By the late eighteen hundreds, 0:03:49.720 --> 0:03:53.640 Prussian blue had found favor with impressionist artists and Japanese printmakers. 0:03:54.120 --> 0:03:56.640 As the nineteen hundreds wore on, it became the hue 0:03:56.640 --> 0:04:01.280 of newspaper inc typewriter ribbon, and eyeshadow. Scientists even discovered 0:04:01.280 --> 0:04:03.920 Prussian blue works as an antidote to heavy metal poisoning 0:04:03.960 --> 0:04:06.960 by acting as a magnet to attract and evacuate heavy 0:04:06.960 --> 0:04:12.000 metals from the bloodstream. Eventually, Prussian blue became as important 0:04:12.040 --> 0:04:15.640 for its practicality as its novelty. But not While John 0:04:15.680 --> 0:04:18.360 Herschel was alive to see it. It wasn't until five 0:04:18.440 --> 0:04:20.880 years after his death that blueprints were recognized as an 0:04:20.920 --> 0:04:26.080 inexpensive and simple way to reproduce architectural drawings. By the 0:04:26.160 --> 0:04:28.840 nineteen seventies, the blue printing process was a dying art 0:04:28.880 --> 0:04:32.240 in the United States because new technology was becoming more prevalent. 0:04:32.839 --> 0:04:35.559 Zerographic copies could create duplicates with the push of a button, 0:04:36.080 --> 0:04:39.440 and by the nine eighties the architecture, engineering, and construction 0:04:39.440 --> 0:04:42.440 industries were making the move from hand drawing to computer 0:04:42.480 --> 0:04:46.680 aided design that could be printed on large scale paper. Today, 0:04:46.880 --> 0:04:50.600 blueprints aren't usually blue. They're most often black or gray 0:04:50.640 --> 0:04:58.560 lines on a white background. Today's episode was written by 0:04:58.600 --> 0:05:01.520 Laurel Dove and produced by a Playing Brain. Stuff is 0:05:01.520 --> 0:05:03.880 a production of I Heart Radio's How Stuff Works. For 0:05:03.960 --> 0:05:06.159 more on this and mons of other original topics, visit 0:05:06.200 --> 0:05:08.760 our home planet, how stuff Works dot com. And for 0:05:08.760 --> 0:05:11.400 more podcasts from my heart Radio, visit i heart Radio app, 0:05:11.520 --> 0:05:14.160 Apple Podcasts, or wherever you listen to your favorite shows.