U and V were one letter in the Latin alphabet Trithemius was ciphering in 1518, and the original Theban set has a single sign covering both. The separate Theban U now in general use is a later supplement, conventionally taken over from the V, but the chart in which it first appears has not been identified and neither has whoever added it. The sign is used daily in modern practice with no known first witness behind it.
What would resolve this A bibliographic collation of printed Theban charts in sequence, from Polygraphiae in 1518 and Agrippa's De occulta philosophia in 1533, through the eighteenth and nineteenth century grimoire reprints, to the twentieth century witchcraft revival, to locate the earliest surviving witness of the supplementary sign and to name the edition that introduced it.
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