There’s the Rub

The children were playing with a toy yacht construction set.  It had hundreds of small plastic parts which interconnect. 

Sammy built a 15-inch long stick which bends when you wave it.

Sammy: (waving his wand) Daddy! Mummy! Look! It’s like rubber…

(Then he noticed that it wasn’t bending at all).

Sammy: … but it doesn’t do much rubbing

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