One can use a thermometer to judge the temperature of a wood fired oven, but with experience people go by eye: soot from the fire collects on the roof and walls of the oven when it's cool, and vaporizes when it reaches a temperature of about 600 F (300 C). So when the roof turns pale it's almost ready, and when the sides of the oven are also pale stone color it's hot -- if you have timed things correctly, something that comes with experience, the fire off to one side will be gentle, and not roaring at this point. If it's too high, let it burn down a bit.
Francesco's wasn't, and he slipped the piglet into the oven, pushing it back towards the back wall, and also put the bean pot in, carefully pushing it to one side.
The beans are of vital importance, because the water absorbs excess heat, and also (by evaporating) gives the oven the proper amount of humidity. You can serve them with the roast -- salt them after several hours -- though Francesco decided to set them aside for future use this time.


