This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Instruments gathers six objects that share no common origin, tradition or material, and that is the honest description of the group rather than a shortcoming of it: what qualifies a thing here is that it was made or used to work with unseen forces or to record a message from them, nothing more specific than that. Three belong to the same documented episode. John Dee's Obsidian Mirror, a polished disc of volcanic glass made by an Aztec artisan before the Spanish conquest and later owned by the mathematician John Dee, The Great Table of the Watchtowers and The Tablet of Union were all part of one working method: Dee's associate Edward Kelley scried into instruments like the mirror while Dee recorded what Kelley reported, and the Watchtowers and the Tablet of Union are grids of letters received that way in the 1580s, the Tablet binding the four elemental Watchtowers into one system rather than being worked on its own.
The other three answer to nothing in that tradition. The Nebra Sky Disc is a Bronze Age bronze disc inlaid with gold symbols usually read as the sun, a crescent and a star cluster, frequently described as the oldest known concrete depiction of the cosmos and recovered only after being looted and then seized in a police sting. The Second Temple Menorah was the seven branched golden lampstand of the Jerusalem Temple, its existence firmly attested by Josephus and by the Arch of Titus relief showing it carried off in 71 CE, after which it vanishes from the record entirely. The Sampo is the object at the center of the Finnish Kalevala, a mill that grinds grain, salt and gold without stopping, whose exact nature the runes never settle and which the atlas records as an open argument. Function, not lineage, is what makes these six one group.