This custom of changing the Signory every second month--a custom maintained to the close of the Republic--has given rise to much discussion. Certainly, this rapid mutation of the highest power in the State could not be favourable to peace; but, as we have had frequent occasion to note, the new constitution of the guilds had reduced the attributes of the central government to a minimum. Besides, the manifest tendency of all Italian republics to degenerate into despotism made the Florentines distrustful of any Signory of longer duration. Now, too, the Ghibellines having returned, there was special cause to fear that the government might be induced to conspire in favour of some ambitious personage disposed to play the tyrant at a moment's notice. For these reasons, it was decided on the one hand to lessen the authority of the Podestà, and on the other to frequently change not only the heads of the government but even, as will be seen, other political functionaries as well. Later on, election by ballot was adopted as another means of preventing the carrying out of any prearranged design against freedom.[314] VI. Meanwhile the King of the Romans was sending his vicar to Italy, with an escort of three hundred men only, to ascertain the temper of the land, and whether the cities still acknowledged the suzerainty of the Empire. On arriving in Tuscany, the vicar made halt at San Miniato al Tedesco, and found the Pisans still Ghibellines, and eager to swear fealty. But when the other Tuscan cities refused to recognise the rights of the Empire the Florentines corrupted the vicar with bribes, and, showing him the futility of his mission, persuaded him to depart acknowledging the force of the privileges granted them by the Pope. Thus they dexterously contrived to make the altered policy of Rome a means of advancing their own interests and damaging those of King Charles, whose power over Central Italy was entirely lost. By once more calling the Empire to the front, and encouraging Rudolph of Hapsburg to assert himself against Charles, Nicholas III. succeeded in weakening both, while giving new strength to the Papacy. So, too, with equal sagacity, the Florentines had made use of the king to dominate Tuscany; of the Pope to enfeeble the king; and, finally, of both to avoid yielding submission to Rudolph.