„The quest for the unity of nature seemed necessarily to go together with a global and co-ordinated approach, able to encompass and measure all types of phenomena. […] To fulfil this programme, Humboldt had to rely on a distributed network of local observers or travellers in the field, in charge of making series of observations and measures that were to be gathered from all over the world and processed into a unique and global science.“ (<bibl xmlns="http://www.tei-c.org/ns/1.0" corresp="https://edition-humboldt.de/26AQMAF5">Bourguet 2002</bibl>, 117).