Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Multi-sized beads, fluorescence. Kevin Mackenzie, University of Aberdeen. Source: Wellcome Collection.
![no text alternative](https://iiif.wellcomecollection.org/image/B0009428/full/800%2C/0/default.jpg)
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Multi-sized beads, fluorescence. Kevin Mackenzie, University of Aberdeen. Source: Wellcome Collection.