Haha wow, I didn't even see that!
The original recipe uses no measurements but "glasses", which I am laothe to do as a scientist, but I do it and it does work.
Mix 4 glasses of water with 2 glasses 100% sourdough starter and 4 glasses of whole grains (I use rye grains). Leave for 12 hours, lightly covered.
Mix in 4 glasses of flour (I use all rye, but you can add some wheat too) and salt. All I can sugest is guessing the salt, as it depends on the size of your glass! Leave covered for another 12 hours.
Spoon the "dough" (more like a paste) into loaf pans (I highly recommend buttered anodised aluminium pans; never had any sticking problems) and leave to prove for 1 hour (any longer and you may get a flying crust).
Bake at 200 degrees C for 1-1.5 hours. You can test it like a cake with a skewer. When cool enough, place the bread into a plastic bag so the residual steam softens the crust and makes it easy to cut. I periodically invert the bag do it doesn't saturate the bread too much.