6 
The Colorado Experiment Station 
to place a washer on each side of the wheel between the spokes and 
the wall, to prevent the wheel from rubbing the sides. 
A cyclometer or bicycle counter made of rust resistant metal, 
which may be purchased for $i.oo or less, is fixed in a recess in 
the side of the wall near one end of the shaft as shown in Fig. i. 
A sixteen penny nail placed through a hole drilled in the shaft about 
a quarter of an inch from the end of the shaft, serves as a pin to 
turn the counter. Injury to or intereference with the counter is 
z-groove for cover plate- 
counter^ 
/ ''pipe^ 
// 
4x4 bearing block' 
// f/ 
4x4- bearing bhck^ 
Figure 1. Arrangement of Counter on Dethridge Meter. 
prevented by a sheet metal plate, one edge of which is set in a 
groove in the bearing block, and the other edge is held by a staple 
and padlock. 
The sheet metal work on the wheel. Fig. 2, is not especially 
difficult, but it should be made in a shop where the necessary ma¬ 
chinery is at hand. The cost of the wheels used in these experi¬ 
ments was $23, $25 and S27.50 for the 4, 5 and 6-foot diameters 
respectively. These costs were for the wheels complete with axles, 
and as they were made largely by hand, it is certain that the prices 
could be lowered from $5 to $to if made in lots of twenty or more. 
The box or structure which contains the wheel, Fig. 3, may 
be made of wood or concrete. Concrete is to be preferred where 
practicable, for it insures the proper clearance being maintained be¬ 
tween the wheel and the box. It is the practice in Australia to 
make the box of concrete sections, which are cast in a central place, 
seasoned, and cemented together after being hauled into the field 
where wanted. 
The Dethridge meter has many points of advantage. It is 
simple, easily understood, records the flow under varying condi¬ 
tions, requires little loss of grade for operation within its normal 
