In case any contention shall arise between the consignee and the carrier in regard to the shortage of coal on any car, the car shall be weighed first while loaded and then the empty car shall be weighed again and the actual gross and net weights shall be ascertained, and the stencil weight of any car marked thereon shall not be taken in any case as a true weight of said car.
Okla. Stat. tit. 13, § 157