Had the public assembly been called upon to act alone without aid or guidance, this accountability would have proved only nominal. But Solon converted it into a reality by another new institution, which will hereafter be found of great moment in the working out of the Athenian democracy. He created the pro-bouleutic, or pre-considering senate, with intimate and especial reference to the public assembly--to prepare matters for its discussion, to convoke and superintend its meetings, and to insure the execution of its decrees. The senate, as first constituted by Solon, comprised four hundred members, taken in equal proportions from the four tribes; not chosen by lot, as they will be found to be in the more advanced stage of the democracy, but elected by the people, in the same way as the archons then were--persons of the fourth, or poorest class of the census, though contributing to elect, not being themselves eligible. But while Solon thus created the new pre-considering senate, identified with and subsidiary to the popular assembly, he manifested no jealousy of the preexisting Areopagitic senate. On the contrary, he enlarged its powers, gave to it an ample supervision over the execution of the laws generally, and imposed upon it the censorial duty of inspecting the lives and occupation of the citizens, as well as of punishing men of idle and dissolute habits. He was himself, as past archon, a member of this ancient senate, and he is said to have contemplated that by means of the two senates the state would be held fast, as it were with a double anchor, against all shocks and storms.