Barnes' Cranioclast This is a cranioclast of the Barnes’ type. Designed by British gynaecologist Robert Barnes, it is a two-bladed instrument with opposed curved blades. The two blades interlock, and a screw joint “elbow” would have been used to secure the locking of the two. One blade is perforated, whereas the other features a ridged pattern to secure grip. Made of metal by “J. Cray & Son Sheffield,” as engraved on one blade, it is a size “11,” as engraved on both. The item appears heavily corroded and rusty. This type of instrument was used in obstetrics to be inserted into the skull of the fetus, brought together to crush the skull, and facilitate the extraction of the fetus. 1875-1925