From Lexicanum

The Melancholia was a symbol used by a faction within the Adeptus Mechanicus.

It consisted of a parchment with the number four arranged in a four by four grid with all the numbers coming to the same answer which was thirty four. This symbol was used by those servants of Adept Koriel Zeth.

Dalia Cythera noticed the parchment on the Mechanicum Protectors belonging to Adept Zeth and realized that she had seen the symbol in some books she had transcribed two years ago.¹

Source

• ¹:Mechanicum (Novel) by Graham McNeill

This article is a stub