On Sun, 27 Feb 2011 21:22:35 -0000, Skipweasel
wrote:

In article ,
says...
As a child, when non-rechargable batteries were all zinc-carbon,
I discovered you could get a bit more use out of them if you
warmed them up in the oven.


I found you could exract the carbon rods and use them with a car battery
to make nice hot arcs. Make a pool of salt and you could smell the
chlorine once it started to melt and electrolyse. Never managed to
isolate any sodium, though.

I made a carbon microphone from a couple of those carbon rods: similar
to Example 1 in this drawing...
http://repo-nt.tcc.virginia.edu/clas...ges/carbon.gif

Nick