Telegraph relay

When the Robinsons introduced the Morse code writer to Hamburg's Börsenarkaden in July 1847, it was no longer a new invention in Europe. However, nobody knew which relay was used to give the Morse telegraph its range. The Robinsons, therefore, took care to keep the rest of their expertise secret and keep the relay hidden inside a box during their presentation. When Charles Robinson became construction manager of the Hamburg-Cuxhaven line, he ensured that its inspector, Clemens Gerke, promised to keep the information confidential.