Chinese tongue diagnosis diagram: 'Black within' tongue
Licence: Public Domain Mark
Credit: Chinese tongue diagnosis diagram: 'Black within' tongue. Wellcome Collection. Source: Wellcome Collection.
![no text alternative](https://iiif.wellcomecollection.org/image/L0039593/full/800%2C/0/default.jpg)
Licence: Public Domain Mark
Credit: Chinese tongue diagnosis diagram: 'Black within' tongue. Wellcome Collection. Source: Wellcome Collection.