Every package containing explosives or other dangerous articles, when presented to a common carrier for shipment, shall have the contents plainly marked on the outside thereof; and it shall be unlawful for any person to deliver, or cause to be delivered, to any common carrier any explosive or other dangerous article under any false or deceptive marking, description, invoice, shipping order or other declaration, or without informing the agent of such carrier of the true character thereof, at or before the time such delivery or carriage is made.