The greatest work, however, of the reign of Servius was the reform of the Constitution, which he constructed with a view to the reconciling of the wide differences between the patricians and the plebeians, so as to form one powerful body by making somebodies of those who had hitherto been treated as nobodies. His first care was to divide the plebeians into thirty tribes--a name derived from the word _tribus_, or three, and applied to the three plebeian tribes--the derivation being so simple that were we to ask any schoolboy if he understood it, his answer would be, that "he might be whipped" and he would assuredly deserve to be whipped "if he didn't." These thirty tribes were placed under an officer called a _tribunus_, whose duty it was to keep a list of the members and collect the _tributum_--a word, to which in the reader's ready mind, the word tribute will at once be attributed. Besides the orders of patricians and plebeians, whose position was determined by descent alone, Servius thought there were many who might be connected together by a tie proper to them all, namely, that of property. He accordingly established a census to be held every five years, in which the name of every one who had come to man's estate was put down, together with the amount of his other estate, if he was lucky enough to have any. The whole number was divided into two heads, one of which was foot, or _pedites_, and the other horse, or _equites_, among whom an equitable share of rights and duties had to be distributed. The _pedites_, or infantry, were not all on the same footing, but were subdivided into six classes, according to the amount of their possessions, which determined their position in the army; but even the sixth class, or those who had no other possession than their self-possession, were not excluded from the service. Each class was divided into seniors and juniors, the former being men between forty-five and sixty; the latter, including all below forty-five and above seventeen, at which early age, though frequently not bearded themselves, they were expected to go forth and beard the enemy. In addition to the two assemblies of the curiæ (the _comitia curiata_) and the tribes (the _comitia tributa_), there was instituted by Servius a great national assembly called the _comitia centuriata_, and consisting of the whole of the centuries. Of these centuries there were altogether one hundred and ninety-three; but, instead of every individual member being allowed a separate vote, the suffrage was distributed amongst classes according to their wealth or the number of asses they possessed, a principle which the opponent of a mere property qualification will regard as somewhat asinine. By this arrangement the poor were practically excluded from voting at all, unless the rich were disagreed among themselves, when the merely industrious classes, such as the _Fabri_--the very extensive family of the Smiths and the Carpenters--the _Cornicines_--the respectable race of Hornblowers--and others of similar degree sometimes had sufficient weight to turn the balance.