Thanks guys
Me, I usually use the rods with a coloured pin attached by a blob of paraffin wax, at regular intervals.
We also have the conductivity "cross thingy" with 4 metals at right angles. Problem with this one is that the wooden circle support may get burned, so is usually done as a dem, with limiting gas to a small flame, but on a hot flame. Using paper clips embedded in wax, with a coloured "flag".
The other conductivity "thingo", is a single unit of 6 radiating rods, one of which is the handle. Fill each of the holes with a cut-off match head, right side up, leaving a little of the wood . Be careful with this one though, demo only, as it can "spit". Always wear protective gear, and cover the bunsen hose with a damp cloth or something. Good effect though.
Oh, and of course the bimetal strip is always a winner
Keep the ideas/methods coming in.....
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