Nothing is more familiar to our ears than the name of the classes and centuries of Servius Tullius; nothing is more difficult, even after the immortal labour of Niebuhr,[c] than to answer all the questions which naturally arise connected with this part of the Roman history. But first of all, in considering the changes effected in the Roman constitution during the later period of the monarchy, we find another threefold division of them presenting itself. We have, first, the enlargement of the older constitution, on the same principles, in the addition to the number of senators and of the centuries of the knights, commonly ascribed to Tarquinius Priscus. Second, we have the establishment of a new constitution on different principles, in the famous classes and centuries of Servius Tullius. And, third, we have the overthrow, to speak generally, of this new constitution, and the return to the older state of things, modified by the great increase of the king’s power, in the revolution effected by Tarquinius Superbus, and in his subsequent despotism. The old constitution was enlarged upon the same principles, in the increase of the number of senators, and of the centuries of the knights. It has been already shown that the older constitution was an oligarchy, as far as the clients and commons were concerned; it is no less true, that it was democratical, as far as regarded the relations of the citizens, or members of the houses, to each other. Both these characters, with a slight modification, were preserved in the changes made by Tarquinius Priscus. He doubled, it is said, the actual number of senators, or rather of patrician houses; which involved a corresponding increase in the numbers of the senate; but the houses thus ennobled, to use a modern term, were distinguished from the old by the title of the “lesser houses”; and their senators did not vote till after the senators of the greater houses. [Illustration: A VESTAL VIRGIN]