any mine in this state and the operator thereof whereby
the miner or loader is to be paid for mining or loading coal other
than on the basis of the ton or other weight according to the total
weight of all such coal contained within the car it shall be the
duty of such miner or loader of coal and his employer to agree upon
and fix, for stipulated periods, the percentage of fine coal
commonly known as nut, pea, dust and slack allowable in the output
of the mine wherein such miner or loader is employed. At any time
when there shall not be in effect such agreed and fixed percentages
of fine coal allowable in the output of any mine, said industrial
commission shall forthwith upon request of such miner or loader or
his employer, fix, such allowable percentage of fine coal, which
percentage so fixed by said industrial commission shall continue in
force until otherwise agreed and fixed by such miner or loader and
his employer. Whenever said industrial commission shall find that
the total output of such fine coal at any mine for a period of one
month during which such mine shall have been operating while the
percentage of fine coal so fixed by said industrial commission has
been in force, exceeds the percentage so fixed by it, said
industrial commission shall at once make, enter and cause to be
enforced such order or orders relative to the production of coal at
such mine, as will result in reducing the percentage of such fine
coal, to the amount so fixed by said industrial commission.

Sec. 978-4. Said industrial commission shall, as to all coal mines
in this state, which have not been in operation heretofore, perform
the duties imposed upon it by the provisions hereof.

=Department of Industrial Relations may change percentage.=

Sec. 978-5. Said industrial commission shall have full power from
time to time, to change, upon investigation, any percentage by it
ascertained and determined or fixed, as provided in the preceding
sections hereof.

=Unlawful to use screen.=

Sec. 978-6. It shall be unlawful for the employer of a miner or
loader of the contents of any car of coal to pass any part of such
contents over a screen or other device, for the purpose of
ascertaining or calculating the amount to be paid such miner or
loader for mining or loading such contents, whereby the total weight
of such contents shall be reduced or diminished unless otherwise
agreed between employer and miner or loader. Any person, firm or