An explorer following his nose  Luca Turin describes his mission
to map the world of smell and a contentious theory of olfactory
perception in The Secret of Scent, says Alex Butterworth The
Secret of Scent by Luca Turin Buy The Secret of Scent at the
Guardian bookshop Public domain  The Secret of Scent Luca Turin
Faber £12.99, pp256  Drinks parties must be a trial for Luca
Turin, a scientist of perfume with an alarmingly acute sense of
smell. Turning up his nose at the illegal scent added to the
champagne to bolster brand loyalty, even the offer of his
favourite negroni cocktail would, one suspects, evince only
momentary gratitude, soon giving way to regret at the
impossibility of capturing a similar feeling of euphoria in
olfactory form. Small talk, too, is destined to frustrate him,
invariably following a well-trodden path to Patrick Suskind's
novel, Perfume, and on to bodily odours and sex. For Turin is an
obsessive on a mission to map an invisible world where he
believes he has unique insights.  'We have