DW>> Making the mill capable of being turned by such a tiny force
 DW>> would be a major challenge!

 GK> That's why they're seldom seen.
 GK> AFAICR we have both kinds in the... well, I'm missing a word
 GK> here. The room next to the physics' lecture hall of an
 GK> university where all the equipment needed for demonstration
 GK> experiments is stored. In German this is simply called
 GK> "Sammlung" (collection). I'll ask a colleague who is working
 GK> there about it next week (about the light mills, not about
 GK> the English language ;-).

Well, I can't help you with the mill, but the room where the collection of
equipment is stored (and also maintained, repaired, and prepared for use)
is called the preparation room.  When speaking of it, we almost always
abbreviate it as "prep room".

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