Architecture: designs for helical (spiral) staircases with twisted iron reinforcing bars. Lithograph by Dunn & Wright.
- Reference:
- 44351i
Licence: Public Domain Mark
Credit: Architecture: designs for helical (spiral) staircases with twisted iron reinforcing bars. Lithograph by Dunn & Wright. Wellcome Collection. Source: Wellcome Collection.
![no text alternative](https://iiif.wellcomecollection.org/image/V0024292/full/800%2C/0/default.jpg)