Virgo

Mercury both owns this sign and is exalted in it, a double claim Adams 1928 says no other sign shares. Lilly 1659 records the same pairing and gives 15 degrees as the exact point. Ptolemy, in Ashmand's 1822 translation, ties the exaltation to the first dryness of autumn and sets the fall of Venus here, across from her exaltation in Pisces.

That oddity prompted a guess. Adams reports esoteric writers who name a hidden planet, Vulcan, as the true ruler. She finds the idea plausible but says her purpose is scientific interpretation, so she works from Mercury. No planet of that name has been found, so the rulership stands on the older assignment.

Alan Leo 1899 calls people of this sign the most critical of all, and adds that they turn the same eye on themselves. Lilly mentions a studious bent and a liking for history, and the 1697 English Manilius lists philosophers, orators and notaries. Modern popular astrology favors the tidy organizer of routines, which keeps the attention to detail and leaves out the scholarship.