501. Duty to issue a bill of lading.

After receiving the goods1 into his charge, the carrier2, or the master or agent of the carrier, must, on demand3 of the shipper, issue to the shipper a bill of lading showing among other things:

  1.  

    (1)     the leading marks necessary for identification of the goods as the same are furnished in writing by the shipper before the loading of such goods starts, provided such marks are stamped or otherwise shown clearly upon the goods if uncovered, or on the cases or coverings in which such goods are contained, in such a manner as should ordinarily remain legible until the