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sonal visit to the Marseilles canal it was learned that this 
module had been abandoned for that reason. 
A simpler device for keeping the orifice a certain distance 
below the surface was tried on the Montrose canal, in the 
western part of the State. The orifice rose or fell with the 
water of the canal, being supported by a float, and was con¬ 
nected with the lateral by a pipe and a flexible joint. The 
trouble in such an apparatus is to make a joint which shall be 
water-tight and at the same time flexible enough to be moved 
by a moderate-sized float when the water rises or falls. If 
this can be done it would satisfactorily solve the problem of 
giving a constant flow. 
A modified form of the Marseilles module, without the 
more objectionable features has recently been invented by an 
Australian. At a competition under the auspices of the 
Minister of Water Supply of Victoria this form received the 
premium of $500. The module consists of a cylinder floating 
vertically, the water passing from the outside to the interior 
of the cylinder as in the case of the Marseilles module, but 
the rim of the cylinder is divided into several notches 
instead of one continuous weir. The cylinder is connected 
with the channel below by a bellows arrangement of leather 
which will open or close as the water varies in depth. The 
am.ount of water is varied by varying the depth to which 
the weirs are sunk in the water. The inventor is Chas. A. 
D’Ebro of Victoria. The durability of the leather may inter¬ 
fere with the success of this module. 
H. L. Decker of South Fork, Colorado, has arranged a 
floating module based on the principle of the siphon, which 
has some good features and would seem to be adapted to give 
a constant discharge. The siphon is arranged to float, so 
that the difference between the level of the water in the canal, 
and the mouth of the siphon remains the same. There is con¬ 
siderable additional apparatus in connection with it for ac¬ 
complishing the object. 
The only module of the second class is one which was 
first placed in operation on the Isabella I. canal of Spain, and 
is due to Senor Ribera. In this one the opening varies in 
size as the depth of water changes, being larger when the 
water is low, and smaller as the water is deeper. The method 
adopted is to allow the water to pass out through a horizon¬ 
tal opening in the bottom of the main canal or the head of a 
lateral. This hole is circular. Through this hole passes a 
plug of metal, which is smaller than the hole, the water pas¬ 
sing between the plug and the outer circumference of the 
opening. By varying the diameter of the plug at different 
