Ab urbe condita
Titus Livius (Livy)
Livy. History of Rome, Volumes 1-2. Roberts, Canon, Rev, translator. London, New York: J. M. Dent and Sons; E. P. Dutton and Co., 1912.
To this class were joined two centuries of carpenters whose duty it was to work the engines of war; they were without arms. The Second Class consisted of those whose property amounted to between 75,000 and 100,000 lbs.
weight of copper; they were formed, seniors and juniors together, into twenty centuries. Their regulation arms were the same as those of the First Class, except that they had an oblong wooden shield instead of the round brazen one and no coat of mail.
The Third Class he formed of those whose property fell as low as 50,000 lbs.; these also consisted of twenty centuries, similarly divided into seniors and juniors. The only difference in the armour was that they did not wear greaves.