/

[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 suffic