The Bone Glass was a relic created in the 19th century by Dr. Edmund Bickerstaff with the help of his associates and his faithful assistant, now known as the Skull. It was buried in Kensal Green with Bickerstaff's body.
It is Dr. Edmund Bickerstaff's legacy - the first gateway to the Other Side.
The Bone Glass was a mirror of about a head's width. Its rim were made of 7 human bones from 7 sprits.
It was said to show enlightenment to whomever was looking at its mirror; but, paradoxically promptly kills the viewer. One glimpse at its mirror causes its victim to be obsessed with it.
Dr. Edmund Bickerstaff lived during the the 19th century. He was a family doctor who would later work in Green Gates Sanatorium, Hampstead Heath, where he treated people with neurological disorder. At the same time he was employed in the sanatorium, he became an occultist in general. He conducted "witchcraft" experiments and robbed graves. His deeds were not kept in complete secrecy yet he was not reproached even by the police; which suggests that he had friends in high places.
He had friends and benefactors and, among them, the aristocrats Simon Wilberforce and Lady Mary Dulac. Sometime in 1877, Bickerstaff and his talented assistant, a male youth, now the Skull, helped him create the Bone Glass. The Skull was the only one who could sense spirits among the group and so his involvement was vital.
On December 13, 1877, the group, implied to be including other curious people, tested the Bone Glass. Skull suggested to Bickerstaff that the eager Wilberforce would be willing to try it. Wilberforce did and died. Dulac and the rest left quickly after the horror. Bickerstaff and Skull followed Dulac to have her look in the glass too. Dulac shot Bickerstaff at the head. Skull escaped. Dulac and co. took Bickerstaff's body back in his estate to conceal the murder. Dulac, haunted by all she saw during the Bickerstaff affair, would also disappear from society. She would be found, 10 years later, living alone in the woods and mad.