![](https://coimages.sciencemuseumgroup.org.uk/284/854/large_thumbnail_a616706__0001_.jpg)
![Brace and bit cranial trephine](https://coimages.sciencemuseumgroup.org.uk/348/150/small_thumbnail_smg00192588.jpg)
![Brace and bit cranial trephine](https://coimages.sciencemuseumgroup.org.uk/2/70/small_thumbnail_a622729.jpg)
Brace and bit cranial trephine
The instrument was used in trephination, the drilling of a hole through the skull bone. The blade creates a circular hole when the brace is turned, much like a standard carpenter’s brace and bit drill. The ornate decoration is typical of 1700s design and unfortunately such features provided a good environment in which germs could thrive. The inscription reads “Eberle”, a surgical instrument maker working in Germany at this time.