Sourdough bread II

I realise this isn't the most interesting photo in the world for other people but it will remind me about this wonderful bread, which is definitely the best bake yet!
A three-day bread.
Day 1 - Make the "sponge" from the sourdough culture (150 g) + 200 g wheat flour and 75 g rye flour + 3 dl water. Stir it vigorously until the gluten starts to stretch out. Cover it and let it bubble away quietly in a corner of the kitchen.
Day 2 (earlyish) - Add another dl of water + 100 g wheatflour - More vigorous stirring - leave to bubble away a bit more. (dl = decilitre = 100 mls)
Day 2 (evening) Make the dough. About 3 dl water, 30 g salt, 500 g flour, wheat, spelt & rye to your taste. Mix it into a fairly soft dough. Stir and then knead well. Cover it one big bowl, or two smaller. It will double in size overnight and it's so embarrassing if it's all over the counter when you come down in the morning so make sure the bowls are big enough.
Day 3 - Knock back the dough, and then split into three equal portions. Shape them and place them in tins. If the dough is drier then you don't need the tins but I prefer a fairly soft dough and so use tins. Brush with water and cover the tins.
Wait until it doubles in size. This can take 45 minutes or it can take 3 hours. Eventually you get a feel for how long it will take. Mine is usually nearer three hours.
Heat the oven up really hot. I usually take it up to about 260°C. Place the bread in the oven and throw a cup of water over the oven base. Turn the oven down to 230°C. Bake until it's done - about 30 minutes or until the internal temperature reaches 95°C.
Remove from tins, tap the base of the loaf to check it makes the right sort of hollow thud.
Leave on a rack to cool as long as you can before the urge to eat fresh-baked bread overcomes you. Eat with lots of butter melting into the hot slices. You can see I don't wait long enough!