with the cavalry upon the wings. But social changes were changing the army. As wealth increased and the gulf between rich and poor grew wider the comfortable burgesses were no longer obedient or willing soldiers. Bad discipline--a monstrous violation of the old Roman spirit--had begun to appear in the ranks as early as the Macedonian wars. In the Jugurthan wars it was deplorably rife. The equestrian class as the richest was also the most mutinous: as early as the third century the knights had refused to work in the trenches alongside of the legionaries. By 140 B.C. they had ceased to act as a military force and become merely a grade of honour, or rather of income, in the state, though the younger knights continued to form a corps of noble guards to the general. As for the army as a whole, the theory down to the time of Marius was still that of the annual spring campaign; each consul levied his own army for a specific purpose. This levy had become more and more difficult. The simple innovation which Marius introduced was that in the process of holding his levy he began by asking for volunteers and enrolling those first. There was generally a distinct promise of rewards on discharge. Thus instead of the moneyed classes Marius filled his ranks with the poorest and hardiest inhabitants of Rome and Italy. Of course the obligation to serve still remained part of the condition of certain subject peoples. The auxiliary ranks were now supplied by foreign experts--cavalry from the Numidian deserts or the Ligurian hills, slingers from the Balearic Islands, and presently archers from Crete. Having thus professionalised his army Marius proceeded to abolish all distinctions in the ranks. All the men of the line now had a uniform equipment supplied by the state, and instead of a bewildering variety of insignia all the legionaries now fought under that emblem destined to be carried in victory to the four corners of Europe--the silver eagle. The eagle was the standard of the legion and it was regarded as sacred. In camp it rested in a special shrine and terrible was the disgrace attaching to its loss in battle. Hitherto legions had been gathered for each campaign and disbanded at its close. Now a legion had a permanent existence, a fixed number, a tradition and an _esprit de corps_ of its own. It was now a larger unit of 6000 men; for while the maniple or company of 120 men still remained, the maniples were grouped into cohorts or battalions, which now became the regular tactical unit, and ten cohorts formed the legion.