Transition of power
Transitions between emperors could be risky times, and Trajan had not clearly defined his successor. We are only a week away from the day that Trajan died, August 8 or 9 in AD 117. On his death bed, he named Hadrian as his successor - at least that is what the letter signed by Plotina said. Hadrian was 41-years-old and decisively took control, and had he not, there might have been another period like AD 69, with 4 emperors competing for the throne, Galba, Otho, Vitellius, and Vespasian.
I have a few coins of Hadrian. I wasn't looking for more, when this historically interesting coin turned up. This is a very early issue of Hadrian securing his transition as successor to Trajan. This coin lacks the word added later, "ADOPTIO", in exergue. However, on this coin the words "DIVI TRAIAN AVG F" declares Hadrian as "son of deified Trajan". Also worth noting that this coin inappropriately carries over the titles of Trajan for Hadrian (e.g. OPT GER DAC PARTH) - titles later not included on coins of Hadrian.
Hadrian, AD 117-138, AR denarius (18.9mm, 3.32g, 7h), Rome mint, struck AD 117
Obv: IMP CAES TRAIAN HADRIAN OPT AVG GER DAC, laureate, draped, and cuirassed bust right
Rev: PARTHIC DIVI TRAIAN AVG F P M TR P COS P P Trajan presenting globe to Hadrian, each holding scroll
Ref:RIC II 2c p.338