Insulation for an Empire: Gutta-Percha and the Development of Electrical Measurement in Victorian Britain

In the second half of the nineteenth century, British engineers and businessmen built the world’s first truly global telecommunications system, a vast network of submarine telegraph cables that reached almost every significant port in the world. Almost all of these cables were insulated with gutta-percha, a natural plastic derived from the latex of Palaquium gutta trees found in Malaya, Sumatra, and Borneo. Cable telegraphy, one of the most technologically advanced industries of the day, was wholly dependent on axe-wielding tribesmen who gathered gutta-percha in the forest. Once it was shipped to London, gutta-percha became one of the most intensively studied substances in the world, its mechanical and electrical properties subjected to minute investigation by leading British physicists and engineers, with far-reaching consequences for the development of electrical science. The story of gutta-percha illustrates important patterns in the appropriation and transformation of tropical materials and their integration into imperial economic and technological systems.