In northeastern India, local tribes have been using rubber tree roots threaded through areca palm canes to build living bridges for 180 years. These bridges can take up to 20 years to grow and can support up to 50 people. They get stronger over time and rarely require maintenance, but the practice has declined in […]
Madder roots, from the Rubia tinctorum plant, produce a bright red dye that was once used for British soldiers’ uniforms. Madder lake, a pigment made from the roots, is more permanent and can be used to tint paints. The chemical compound responsible for the pigment, alizarin, was discovered in 1868 and replaced the need for […]
