The limitation of time for unlading shall not extend to vessels laden exclusively with merchandise in bulk consigned to one consignee and arriving at a port for orders, but if the master of such vessel requests a longer time to discharge its cargo, the compensation of the inspectors or other customs officers whose services are required in connection with the unlading shall, for every day consumed in unlading in excess of twenty-five days from the date of the vessel’s entry, be reimbursed by the master or owner of such vessel.