emil müller proposed in 1831 the construction of a railway line between hamburg and lübeck, connecting the north and the baltic seas, but finding little support in lübeck, he travelled to london in 1833, where he eventually found investors. müller recruited as senior engineer francis giles, the chief engineer of the newcastle and carlisle railway (1829–1836). marc isambard brunel and his son isambard kingdom brunel, the designer of london's thames tunnel (1825–1843) also offered their services to müller. in september 1833, giles' assistant william lindley travelled to hamburg. he would later lead the successful construction of the berlin-hamburg railway and the hamburg urban drainage scheme. he began surveying the line on 6 november 1833. although the line would have to run through holstein-glückstadt, which was ruled by the king of denmark, lindley decided not to submit an application to the danish authorities for approval for this survey work prior to carrying it out in order to save time.