Geissler tubes with a complicate design.
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Geissler tubes with a complicate design. Wellcome Collection. Source: Wellcome Collection.
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Geissler tubes with a complicate design. Wellcome Collection. Source: Wellcome Collection.