Diagram of the double microscope of P. and J. Dolland, opticians, in St. Paul's Church Yard, London. 18th to 19th century.
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Diagram of the double microscope of P. and J. Dolland, opticians, in St. Paul's Church Yard, London. 18th to 19th century. Wellcome Collection. Source: Wellcome Collection.