Q = 32.8, hence

       Q
  v = —–­ = 2.43;
       a

[TEX:  v = \frac{Q}{a} = 2.43;]

and

/              {1/2} \
n ( in v = n (r s)^    ) = 33.
\                  /

[TEX:  n\ (\text{in}\ v = n (r s)^\frac{1}{2}) = 33.]

The flume is of unplaned boards, rectangular, 2.67 wide x 2.83 deep, with an inclination of 32 feet per mile.  There are sharp curves, although these were made as regular as practicable; the boiling action of the water passing around these curves brought the flow line (Q = 32.8) nearly up to the top of the sides; with a straight flume of the same size, the water would have doubtless stood several inches lower.

Therefore: 

a = 2.67 x 2.83 = 7.56 ;

a
r =  -------------------- = 0.908 ;
2.83 + 2.67 + 2.83

[TEX:  r = \frac{a}{2.83 + 2.67 + 2.83} = 0.908;]

32       1
s =  ------ = ----- ;
5280     165

[TEX:  s = \frac{32}{5280} = \frac{1}{165};]

Q = 32.8, hence

Q
v = —–­ = 4.34;
a

[TEX:  v = \frac{Q}{a} = 4.34;]

and n = 59.

With the pipe,[6] 1.416 diameter,

d
r = —–­ = 0.354; Q = 31.69; v = 20.13.
4

[TEX:  r = \frac{d}{4} = 0.354;\ Q = 31.69;\ v = 20.13.]

[Footnote 6:  Vide pages 120-122, Transactions American Society of Civil Engineers for 1883.]

Allowing for loss of head due to imparting velocity to water, and for contraction,

296.1
s= --------; and n = 131.
4438.7

[TEX:  s = \frac{296.1}{4438.7};\ \text{and}\ n = 131.]

We hence have the following values of n, in v = n (r s)^{1/2}, Q being constant: 

Rough ditch, with sharp curves. 33 Rectangular flume, with sharp curves. 59 Wrought-iron pipe, with easy curves, coated with asphalt, but with rivet-heads forming noteworthy obstructions (m = 65.5, and 2m = n) 131

* * * * *

PARACHUTE HYDRAULIC MOTOR.

The very singular and simple hydraulic motor which we illustrate herewith is the invention of a Russian engineer, Mr. Jagn.  It is scarcely as yet known in Western Europe, where, however, something will probably be heard of it ere long.  Its true field would seem to be Egypt, India, or any country where canals or rivers are used for irrigation, and where it is desired to draw water from them at particular spots in the simplest and cheapest manner.  At present in nearly all such cases water is raised by hand or steam power; nevertheless it must be obvious that the current of the canal itself, slow though it may be, is quite sufficient to raise a small portion of the discharge to the very moderate height generally needed to lift it over the banks into the adjoining fields.  Why then is it not employed for the purpose?