The coefficient of efflux is 61.6 per cent. These figures are within the limit of 1/100 possible error.*
As
the two-inch aperture requires too much space for gauging large
quantities of water, custom has changed the form of the module, and an
aperture twelve inches high by twelve and three-quarter inches wide,
through a one and one-half inch plank, with a head of six inches above
the top of the discharge, is now used. These openings discharge what is
accepted as 200 miner's inches.
A
series of experiments was made at La Grange, Stanislaus County,
California, latitude 37° 41' N., elevation 216 feet above the level of
the sea, to determine the value of the inch thus delivered in the
claims. The results here given are the mean of a series of gaugings
* The experiments were made in 1874 by H. Smith, Jr., C.E.
