When stiring soup or porridge and the like you can see the effectiveness by the reduced release of steam bubbles. 

I have thought just plain circular stiring may not be the best as it could leave the outside and inside content permanently outside or inside. However, trying figure eight and different methods all appear less effective than simple circular stiring.

Is there any best way to stir liquids?

What is the significance of James Bond's famous phrase "shaken not stirred"? Is there really a difference in the taste of a shaken vodka martini, as opposed to a stirred one? And if so why?

(Continued)

What is the significance of James Bond's famous phrase "shaken, not stirred"?

Is there really a difference in the taste of a shaken vodka martini, as opposed to a stirred one? And if there is, why?

Mark Langford, Stockport, Cheshire

The shaken-versus-stirred dispute has run for years in The Last Word. One of our books, How to Fossilise Your Hamster, drew on the first three answers below to explain the differences. However, we have since learned that other chemical reactions may be taking place - Ed

I observed some years ago that if, having first stirred a mug of hot-chocolate one taps the bottom of the mug from within with a metal teaspoon the note given off rises quite distinctly with each tap. I have not reproduced the same effect with tea or coffee. However, any normal ceramic mug and brand of drinking chocolate seems to produce the effect. What, if any, are the special properties of hot-chocolate that produce this rising note effect?