Most old farmhouses in North Devon would once have been equipped with cloam ovens like this one. Made of local clay, they were still being manufactured in various standard sizes as late as the 1930s.
The word cloam just means clay. William Fishley Holland describes how they were made at the Fremington Pottery:
“The oven was made by hand, first treading the clay on the wood floor and shaping with an iron frame like a horseshoe. Then the back portion was trodden out, raised on end and the board trigged up until the front had been made. This too was raised and the two ends joined, forming a ring. This was manipulated to the correct shape and domed in until it could be closed over. Sometimes it was necessary to add to the height, and this was done by putting thick rolls of clay on the ring and working it up… When stiff enough, the door would be cut out, fitted with handle and replaced.”
To cook in a cloam oven you make a fire of sticks inside to heat the oven up, until a stick scratched on the top produces sparks. Then sweep it out and put your loaves of bread or meat inside, sealing the door until it is cooked.
Cloam ovens were often hidden when houses were fitted with ranges in the late 19th century. Now they are often opened up as decorative features. If there is a tell-tale bulge on the outside wall of your house there might be one in your fireplace!