Querns and grinding
- I'm not quite sure from the correspondence that has been posted whether people realise that the stones were only one part of the quern. From the discussion of the stones jamming, possibly not. There were also iron fittings in the flat quernstone - the rynd which goes across the bottom of the upper stone through which the spindle fitted. This means you can adjust the space between the stones for different grades of meal / flour etc.
It was suggested in an earlier message posted on Wednesday that the beehive quern would have been more efficient. this is not supported by the archaeological evidence. People obviously preferred the flat form once it had been introduced. Beehive querns did remain in use but I suspect they were for specialised products. Certainly in Britain, it is fragments from flat stones that predominate in Roman contexts.
At the risk of a bit of self advertisement you'll find this all discussed on pp. 71-74 of my Eating and Drinking in Roman Britain which also has discussions of length of time it takes to grind things, the relationship of beehive querns to flat querns etc.
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