Gartner's tonometer.
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Gartner's tonometer. Wellcome Collection. Source: Wellcome Collection.
![no text alternative](https://iiif.wellcomecollection.org/image/L0004529/full/800%2C/0/default.jpg)
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Gartner's tonometer. Wellcome Collection. Source: Wellcome Collection.