PAL

Ptolemaeus Arabus et Latinus

_ (the underscore) is the placeholder for exactly one character.
% (the percent sign) is the placeholder for no, one or more than one character.
%% (two percent signs) is the placeholder for no, one or more than one character, but not for blank space (so that a search ends at word boundaries).

At the beginning and at the end, these placeholders are superfluous.

Giovanni Antonio Magini, De annui temporis mensura in directionibus et de directionibus ipsis ex Valentini Naibodae scriptis

Frankfurt/M., Wolfgangus Richterus, 1608 · 162

Facsimile