This process is a blend of two chemicals than become UV sensitive. Brush the UV sensitive liquid on to watercolor paper. After the paper dries ( or while still wet for the 'wet cyanotype' method) expose to bright sunlight using a photo negative or found objects. Rise print in mixture of water and hydrogen peroxide. This will create the most beautiful Prussian blue print.
The English scientist and astronomer Sir John Herschel discovered the procedure in 1842. Though the process was developed by Herschel, he considered it as mainly a means of reproducing notes and diagrams, as in blueprints. Anna Atkins created a series of cyanotype limited-edition books that documented ferns and other plant life from her extensive seaweed collection, placing specimens directly onto coated paper and allowing the action of light to create a silhouette effect. By using this photogram process, Anna Atkins is sometimes considered the first female photographer.