The children grew up, and people began to talk of a successorship to Augustus in the Principate.  It would be, of course, through Julia, his daughter.  He married her to Marcellus, aged seventeen, his sister Octavia’s son, who he adopted.  Marcellus and Julia, then, would succeed him; no one thought of retiring Tiberius.  Marcellus, however, died in a couple of years; and folk wondered who would step into his place.  Augustus gave Julia to Vipsanius Agrippa, the man who had won so many campaigns for him.  Agrippa was as old as the Princeps, but of much stronger constitution; and so, likely to outlive him perhaps a long while.  Very appropriate, said Rome:  Agrippa will reign next:  an excellent fellow.  No one thought of shy Tiberius.—­Agrippa, by the way, was a strong man and a strict disciplinarian,—­with soldiers, at any rate:  it might be hoped also with wives.  It was just as well for lady Julia to be under a firm hand.

Ten years later Agrippa died, and the heirship presumptive passed to his two eldest children by Julia:  the princes Caius and Lucius.  Augustus adopted them in due course.  Heirship presumptive means here, that they were the ones Rome presumed would be the heirs:  a presumption which Augustus, without being too definite, encouraged.  The Initiate Leaders and Teachers of the world do not, as a rule, as far as one can judge, advertise well beforehand the identity of their successors.—­As for Tiberius;—­why, said Rome, his stepfather does not even like him.  Drusus, now, and his children,—­ah, that might be a possibility.

For the marriages of the two brothers told a tale.  Drusus had married into the sacred Julian line:  a daughter of Octavia and Mark Anthony; his son Germanicaus was thus a grand-nephew of Augustus, and a very great pet.  But Tiberius had made a love-match, with a mere daughter of Agrippa by some former wife:  an alliance that could not advance him in any way.  Her name was Vipsania; the whole intensity of his pent-up nature went into his feeling for her; he was remarkably happily married;—­that is, for the human, the tender, sensitive, and affectionate side of him.

Meanwhile both brothers had proved their worth.  At twenty-two, Tiberius set up a kind in Armenia, and managed for Augustus the Parthian affair, whereby the standards of Crassus were returned.  There were Swiss and German campaigns:  in which Drusus was rather put where he might shine,—­and he did shine;—­and Tiberius a little in the shade.  But Drusus in Germany fell from his horse, and died of his injuries; and then Tiberius was without question the first general of his age, and ablest man under the Princeps.  As a soldier he was exceedingly careful of the welfare of his men; cautious in his strategy, yet bold; reserved; he made his own plans, and saw personally to their carrying out;—­ above all, he never made mistakes and never lost a battle.  His natural shyness and timidity and awkwardness vanished as soon as there was work to be done:  in camp, or on the battlefield, he was a very different man from the shy Tiberius of Roman society.