Okla. Stat. tit. 66, § 88
Shippers or consignees on whose order a car or cars of less than sixty thousand (60,000) pounds capacity have been placed for loading or unloading, shall have forty-eight (48) hours for loading or unloading such cars and seventy-two (72) hours for loading or unloading those of sixty thousand (60,000) pounds or greater capacity, computing time from seven o'clock a.m., of the day after such car or cars have been placed subject to such order; and thereafter a demurrage charge of not more than One Dollar ($1.00) per car per day or fraction of a day, may be assessed and collected on all such cars respectively as have not been tendered to the railroad company, with shipping instructions for loaded cars, within said respective periods of forty-eight (48) hours and seventy-two (72) hours of free time: Provided, however, that should such shipper or consignee fail to begin loading or unloading within forty-eight (48) hours after the expiration of free time the railroad company may consider the empty car or cars released, and may assess and collect on every car, loaded or empty, One Dollar ($1.00) covering the demurrage then due, and nothing herein shall be construed as meaning that demurrage is a lien on the freight: Provided, that when by reason of delay or irregularities on the part of the railroad company in filling orders for cars, or in the transportation or delivery of freight, cars are bunched in excess of the capacity of the shipper to load, as indicated in his application or of the consignee to unload, such shipper or consignee shall have separate and distinct periods of free time in which to load or unload as the case may be, the car or cars specified in each separate application, or in each bill of lading or waybill of different dates.
R.L. 1910, § 1418.