burghers remained peaceable beneath his sway and refrained from
attacking him in person, he was mild. But at the same moment the
gallows, the torture-chamber, the iron cage suspended from the giddy
height of palace-roof or church tower, and the dreadful dungeons, where
a prisoner could neither stand nor lie at ease, were ever ready for the
man who dared dispute his authority. That authority depended solely on
his personal qualities of will, courage, physical endurance. He held it
by intelligence, being as it were an artificial product of political
necessities, an equilibrium of forces, substituted without legal title
for the Church and Empire, and accumulating in his despotic
individuality the privileges previously acquired by centuries of
consuls, Podestàs, and Captains of the people. The chief danger he had
to fear was conspiracy; and in providing himself against this peril he
expended all the resources suggested by refined ingenuity and heightened
terror. Yet, when the Despot was attacked and murdered, it followed of
necessity that the successful conspirator became in turn a tyrant.
'Cities,' wrote Machiavelli,[2] 'that are once corrupt and accustomed to
the rule of princes, can never acquire freedom, even though the prince
with all his kin be extirpated. One prince is needed to extinguish
another; and the city has no rest except by the creation of a new lord,
unless it chance that one burgher by his goodness and great qualities
may during his lifetime preserve its temporary independence.' Palace
intrigues, therefore, took the place of Piazza revolutions, and
dynasties were swept away to make room for new tyrants without material
change in the condition of the populace.

[1] _Mur. Scr. R. It._ xv. 826. Compare what G. Merula wrote about
Azzo Visconti: 'He conciliated the people to him by equal justice
without distinction of Guelf or Ghibelline.'