178 
Italian Irrigation. 
Vettabbia for the irrigation of their meadows, and jealously "and 
vigorously maintained their claims, until, finally, they secured the 
sanction of the government. 
From this period the era of canals commences. They are the 
works of emancipated Italy ; in many instances the memorials 
of special victories, the Canale della Battaglia, in particular, 
commemorating the overthrow of Barbarossa at Legnano. 
V. — Tlie Naviglio Grande. 
It may be instructive briefly to trace the history of some one 
canal, and the Naviglio Grande, which conveys the waters of the 
Ticino to Milan, may serve us as a specimen. This work, which 
now fulfils the double purpose of navigation and irrigation, 
appears to have been designed for the latter object as early, if 
not earlier, than 1177 : a charter of the Abbey of Chiaravalle, 
dated 1233, shows that Milan was then connected with the 
Ticino by a channel, part of which Avas navigable ; in 1272 
Torriano, the Guelphic chief of Milan, made it navigable 
throughout ; in 1329 this canal played a prominent part in the 
discomfiture of Frederic II., its waters being diverted so as to 
flood his entrenched camp. " The history of the Naviglio Grande 
for a century after its completion is a continued record of 
discontents and disputes regarding the supply of water." No 
regulations had been at first laid down for the distribution 
or measurement of the water ; the rules afterwards proposed 
were arbitrary and unsatisfactory ; practically the law of the 
stronger prevailed, whilst the Visconti, then Lords of Milan, 
favoured the privileged classes, whether noble or religious, and 
made reckless grants to reward private services or purchase 
support. ' 
When, however, in 1376, Jean Galeazzo Visconti made an 
attempt to regulate the outlets ; and yet more, when, in 1446, 
Filippo Maria Visconti published an ordinance annulling at 
once all existing water rights, such .i fearful tumult arose as 
foiled even these despotic rulers. In 1503, when Milan was in 
the hands of Louis XII. of France, the magistracy issued a 
decree, ordering that all the outlets should be reduced to a 
uniform height of 4 inches ; that they should be cut in a single 
piece of stone 3 inches thick ; that each outlet should be fur- 
nished with a chamber about 16 feet in length ; and that the sill 
of the outlet should be fixed at 1-92 feet above the level of the 
bottom of the canal : how far these regulations were acted on is 
very doubtful. In the troubled times which saw the defeat of 
Francis I. at Pavia, and the transfer of Milan to Spain, the 
