Antique French Delachanal Paris mailbox. In order to encourage small towns to install additional mail boxes, Delachanal created for the post office a large steel box utilizing the same door as the cast iron boxes. The new mail box had a pressed steel pyramid roof and simple straight sides and canted corners. There was a similar flap to the small steel boxes. These boxes are quite unusual as the drain holes in the bottom frequently blocked, allowing the bottoms to rust out.