On Wednesday last at about 4:15pm I walked round to post a letter at the  box 
outside our recently closed Post Office. I heard a strange noise nearby  like 
a cement mixer filled with broken bottles and climbed up to the picnic  area 
nearby to investigate. It was the sound of a narrowboat grinding its  way 
through inch or more thick ice past a row of moored boats (including some  
plastic 
cruisers) and its prop chewing up the broken ice left behind. The  intrepid 
crew were managing to progress at the rate of about 5 metres per  minute. I was 
surprised that they were going on in the gathering gloom with  about two 
miles to the next possible mooring place as they were just passing a  free BW 
mooring (all facilities, and the adjacent Boat Club bar open that very  
evening).
 
In the Club House later in the evening there was much talk of  the un-named 
'blue' boat' (cue comment from Beeky re the Un-fleet) being on  the move in 
such conditions and not stopping to enjoy the local facilities and  
conviviality.
 
AND ANOTHER THING
 (but please excuse these ramblings if someone more scientifically  qualified 
than I has already resolved the water below the lock  problem.)  
 
On the subject of the water below locks being un-frozen whilst there is ice  
in the lock and in the pound above; doesn't this have more to do with the  
density properties of water rather than potential energy being converted to 
heat  
via kinetic energy? Water is at its densest at 4deg C if I remember, so  
warmer or colder water than that at 4 deg. would both rise, consequently  water 
at 
the bottom of a full lock would be at a higher temperature than the ice  
above it and therefore water leaking out of the bottom would be (relatively)  
warmer than the temperature at which ice would form on the surface in  the 
pound 
below the lock. Also the water close to the bottom of a lock will be  more 
sheltered from the wind than the more exposed surface water giving yet  another 
possible explanation.
 
Arthur Naylor
nb Warm at Home


[Non-text portions of this message have been removed]

Reply via email to