Abstract: This oven has a primary heating chamber containing heat-generating equipment producing hot gases. These gases pass from the primary heating chamber to a secondary heating chamber occupied by an indexing rotary magazine in object-exchanging relationship with a mechanism for inducing movement of the objects through the oven. The secondary heating chamber can be used for either pre-heating or heat-soaking the objects, depending on the direction of movement of the objects through the oven. The objects are loaded on the carrier (or removed, according to the application of the oven) radially at a position angularly spaced from the position of exchange with the movement-inducing means.