[Illustration: EMPRESS THEODORA AND COURT, RAVENNA. [_To face page 404._] What has been said will put in a clear light the extraordinary importance accorded to the University and the professors of Bologna in connection with their labours in annotating and interpreting the _Corpus iuris_ so as to make it intelligible to all, and an instrument for instructing and training all those who sought to follow the legal profession, whether as notaries, judges, Podestàs, or captains of the people. That these teachers possessed a very slender knowledge of history is seen from their writings. Their merit lay in the intelligent exposition of a system of law which had never become extinct. It was a precept of theirs that "as the unskilled rider must hold on by the pommel, so the judge should stick to the gloss." In this way the school of Bologna became, as it were, the depository of an universal law which was looked upon as almost sacred. Thither popes sent their decretals, emperors their edicts for registry or revision. The Emperor was, however, regarded as the living source of legislation, as alone entitled to add new laws to the Roman. Any one speaking evil of the Emperor met with condign punishment. Any one who questioned his universal authority was declared heretical by the jurists themselves. This authority belonged to him as lord of all nations, and was transmitted to him from the Roman Empire as its rightful heir. It was natural, therefore, that to determine the extent and limits of this authority, recourse should again be had to the professors of Bologna, the veritable depositaries of the Roman law, who accordingly acquired a constantly increasing importance. The _ratio scripta_ was what was always called for; and the communes, even while avowing their determination to preserve their ancient liberties undiminished, never forgot to profess their willingness to leave the Emperor all the _veteres justitias_ which belonged to him, and which they declared themselves desirous to respect. The only question was to ascertain what these were, and hence fresh occasion to consult the professors of Bologna.