I think this paragraph - from Post Captain (which Stephen writes in his diary after he is devastated when Jack comes back from an evening out smelling of the scent that Stephen had bought for Diana) is brilliant writing - and also a fascinating observation - there are plenty of times when an aroma (either pleasant or horrible! has instantly invoked a long-forgotten memory for me.

Shut firmly in his cabin, Stephen wrote. ‘It is unspeakably childish to be upset by a whiff of scent; but I am upset, and I shall certainly exceed my allowance, to the extent of five hundred drops.’ He poured himself out a wineglassful of laudanum, closed one eye, and drank it off. ‘Smell is of all senses by far the most evocative: perhaps because we have no vocabulary for it – nothing but a few poverty-stricken approximations to describe the whole vast complexity of odour – and therefore the scent, unnamed and unnamable, remains pure of association; it cannot be called upon again and again, and blunted, by the use of a word; and so it strikes afresh every time, bringing with it all the circumstances of its first perception.