I am a home baker and I have been cooking for the last 55 years. Now that I am a retiree I want to refine the art and make not just good bread but really great bread. Which leads me to my question concerning the preferment called a sponge. In my studies I have noticed a wide difference in the hydration rate for sponges. Example: Rose Levy Beranbaum, in her book "The Bread Bible" page #32 she says,"I usually make a sponge with equal VOLUMES of flour and water. This is about one and a half times the weight of the flour in water ( 151% hrdration." Ok, now listen to what Daniel T. DiMuzio says in his book "Bread Baking: An Artists Perspective" page #69, "Sponge is often the name applied to stiffer mixtures of flour, water and yeast that are fermented ahead of time. The hydration level of sponges made from North Americican flour is usually 60-63% and they can be fermented for 5-24 hours". And, James Peterson in his book "Baking" page 285 says, " A classic sponge is equal parts flour and water by VOLUME is typical." So, we can see that Beranbaum and Peterson are in agreement with a very liquid sponge, BUT DiMuzio's sponge is extremely stiff , at least as stiff "old dough" Far be it from me to find fault with such professionals but it is confusing. When I make a more liquid sponges and put them in the fridg the flour and water separates and the sponge just sits there and does nothing. When I make the stiffer sponge and put it in the fridg it puffs somewhat but not a lot. I am wondering how two very different preferments can both be called a sponge? And also,I'd be interested to know how different bakers handle the sponge (at room temp or in the fridg). Thanks for your in-put.