The National Archives hold an incredible wealth of textual documents that are used by historians, and it’s common to find academics poring over medieval court rolls or World War I government records. What is less well known is their visual documents, especially the designs for patents registered after 1842. These cover all imaginable products, from pins to steel smelters and from ribbons to horse blankets. Where possible, samples of the products were preserved along with the patent registration, and bound into bulging leather-clad volumes weighing up to 10kg. The archive is trying to encourage designers to use this resource, and has posted some reinterpretations of historic designs on its website. The butterflies below are labelled with the reference numbers of the original designs – BT standing for Board of Trade.
http://www.nationalarchives.gov.uk/imagelibrary/creative-images-showcase.htm
Butterflies using textile designs from Board of Trade registers, The National Archives