Public Domain Mark
You can use this work for any purpose without restriction under copyright law. Read more about this licence.
Credit
M0005932: Nitrous oxide gas apparatus, from Coxeter: <i>Catalogue of Surgical Instruments and Aparatus</i> (1870) / M0005933: Nitrous oxide gas apparatus, from Coxeter: <i>Catalogue of Surgical Instruments and Aparatus</i> (1870). Public Domain Mark. Source: Wellcome Collection.