The appeal to the people,[34] which might annul the judgments of the magistrates, was nothing more than the appeal to the curia; and it was by having recourse to it, after having been condemned by the decemvirs, that the survivor of the three Horatii was saved. The policy of the kings consisted in blending together the different races and breaking down the barriers which separated the different classes. To effect the first of these objects, they divided the lower class of the people into corporations,[35] and augmented the number of the tribes and changed their constitution;[36] but to effect the second, they introduced, to the great discontent of the higher class, plebeians among the patricians,[37] and raised the freedmen to the rank of citizens.[38] In this manner, each curia became considerably increased in numbers; but, as the votes were taken by head, the poor patricians were numerically stronger than the rich. Servius Tullius, though he preserved the curiæ, deprived them of their military organisation, that is, he no longer made it the basis of his system of recruiting. He instituted the centuries, with the double aim of giving as a principle the right of suffrage to all the citizens, and of creating an army which was more national, inasmuch as he introduced the plebeians into it; his design was indeed to throw on the richest citizens the burden of war,[39] which was just, each equipping and maintaining himself at his own cost. The citizens were no longer classified by castes, but according to their fortunes. Patricians and plebeians were placed in the same rank if their income was equal. The influence of the rich predominated, without doubt, but only in proportion to the sacrifices required of them. Servius Tullius ordered a general report of the population to be made, in which every one was obliged to declare his age, his fortune, the name of his tribe and that of his father, and the number of his children and of his slaves. This operation was called _census_.[40] The report was inscribed on tables,[41] and, once terminated, all the citizens were called together in arms in the Campus Martius. This review was called the _closing of the lustrum_, because it was accompanied with sacrifices and purifications named _lustrations_. The term _lustrum_ was applied to the interval of five years between two censuses.[42] The citizens were divided into six classes,[43] and into a hundred and ninety-three centuries, according to the fortune of each, beginning with the richest and ending with the poorest. The first class comprised ninety-eight centuries, eighteen of which were knights; the second and fourth, twenty-two; the third, twenty; the fifth, thirty; and the sixth, although the most numerous, forming only one.[44] The first class contained a smaller number of citizens, yet, having a greater number of centuries, it was obliged to pay more than half the tax, and furnish more legionaries than any other class.