Hi Jim
On (02 Nov 97) Jim Dunmyer wrote to Dave Halliday...
 > Most of the recent large ships are diesel-electric.  Works great 
 JD>  Thanks for the feedback on that. I've been on a number of older ships,
 JD> but didn't realize that new ones now use electric drive.
Ships of the Castle Line [1930s- 1940s] were DC driven. The large dynamo[s]
had exposed commutators. My cousin Douglas Kaye was elec officer on "Stirling
Castle" in 1945. His Chief would lovingly "caress" the spinning comm lightly
with the palm of his hand, on morning inspection.
He felt no pain, because he touched the "neutral" zone of the comm, at a
discrete distance from the ungrounded brushholder.
One day a junior elec officer, was the duty man- and on this day one of the
Owners was aboard. Junior to impress the big wig, did the comm caressing 
rick
but touched the wrong part of the comm surface, and was thrown noisily and
painfully, across the machine room floor.
In Melbourne 1950, I visited "Stirling Castle" during a minor piston repair. 

Lascar mechanic was seated on top of a piston while it was still in the
cylinder, examining the bore. These had DOXFORD engines- two pistons per
cylinder, running in opposition. I guess that reduced the vibration quite a
deal.
Around that time I worked on steel tank mercury arc valves, rated 3000kW. We
were required to work in stockinged feet, when inside the valve. My hair is
white now! Not only was mercury in there for the arc to function, but each
valve had a mercury pump in order to sustain a hard vacuum.
The negative bus, ran thru a large choke about six foot dia, beside a 
alkway.
It was fun to walk past while carrying a steel bucket!! Gravity became
horizontal.......
Cheers........ALEC
... Wunce i coodn even spll ingineer. Now i are wun!!
--- PPoint 1.92
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