I recall visiting St Mary’s lighthouse in Whitley Bay as a young adult and being shown the lantern room. The light apparatus weighing about 2 tons (if memory serves) was floating on an open trough of mercury and we were invited to push the whole thing around. It moved with virtually no effort. Trinity House were very proud of that. Probably wouldn’t be allowed to do that today.
Yup, it’s coming back to me now. It was lighthouses.
The telescope thing was, in a way, even neater. It turns out if you have a circular tank of mercury you can make a parabolic mirror simply by rotating it. Centrifugal force ‘throws’ the mercury out towards the tank edge where, crudely put, it ‘piles up’ into a paraboloid. You have to worry a bit about ripples and about debris falling onto the surface, but it’s a relatively cheap way of making a very large mirror whose surface is pretty much impossible to damage. You can only look straight up though.
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Yes, istr that there have been mercury-filled interconnects.
And mercury rectifier valves.
Years ago a very drunk @Coco was musing on using them in my amps.
“If you have a bucket of sand and some breathing apparatus you should be alright if something goes wrong” he said. “They are very pretty!”
We ended up with Mullard GZ33 
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Could still add a mercury tungar power supply?
Paging @murrayjohnson
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Why is spaghetti this weeks theme?
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I would say empty nut sack.
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Stent.
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Is that an instruction?
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Cables with built-in lifters - bargain!
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Guessing if you can’t hear the difference,you have some ready made mini lobster pots
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For @Ruprecht
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Post of the day
“Resonant sausage meat”
It is a shame forum ethos posts are still verboten.
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