— 5 — 
governing the flow of water, the principles involved in distri¬ 
bution and measurement are the same here as there. We 
ire finding the necessity of laws and regulations which they 
ong ago found necessary. We shall find it necessary to take 
)ther steps which their experience long ago showed desirable. 
The Italian modules have been various, but until recently 
nost of them have been based upon one idea—an erroneous 
)ne —which has been introduced into Colorado and the other 
vestern states in the form of the various miners’ inches. 
The need for measurement was felt befoie. theie was 
nore than the most limited knowledge of hydraulic laws, and 
:he methods of measurement date back, consequently, before 
che rise of hydraulic science. That they have been used tor 
several centuries with even a fair degree of satisfaction re¬ 
flects great credit upon Soldati and the magistrates of Mdan 
who so firmly grasped the conditions of the problem. 1 hat 
these measures are known to be incorrect is shown by the tact 
that all of the large modern canals have adopted other systems. 
The Cavour Canal, the Canale Casale, the Canale Villorsi 
have all adopted systems depending upon the weir. I he in¬ 
sufficiency of the old measurement is evidenced by the tact 
that the Italian government required in one of its acts ot 
concession granting water to a new canal, a plan for a new 
module for the measure and sale of water. That the old 
measures are still used, and will be used, is due. to 
the fact that in time the individual users have acquired 
rights in the water which that particular method allows them, 
and any change which threatens those rights arouses at once 
intense opposition I he same kind of conservatism is shown 
in Colorado, and the same varied customs are growing up. 
There are already numerous canals on which there are sev¬ 
eral different methods of .measurement in use and where 
water is measured out differently to the early users. I he 
changes affect the new users. 
The module proposed and adopted by this canal the 
Canale Villoresi—will be especially described because it 
seems to dispose of some of the difficulties which have made 
the weir objectionable. 
In the measurement of water there . are two distinct 
classes of measuring boxes, different in their object. One is 
the dividing box, whose object is to give to each consumer 
some definite portion of the water flowing in the ditch. 1 is 
box is found especially in the laterals owned in common y 
two or three neighbors, or in the smaller canals owned and 
operated by the stockholders. The other class is the meas- 
