This book would have been far more difficult to write if it hadn’t been for the support, advice,
and encouragement of a number of key people. Thanks are especially due to Deike Begg and
to Anne Gamble. I’d also like to thank Jennie Harding for the moisturising gel recipe quoted
on page 46; Sophie Darragh for babysitting at short notice; Lesley Bacon, Susan Yadlon and
Annette Van for their support and encouragement and my current and former students for their
willingness to donate their bodies to science as they tried out blends and asked a lot of complicated
questions in the process. You have all helped me to hone my ideas and keep the explanations
(relatively) simple. Lastly, this is, as always, for Alan and Hannah.