Perhaps a different sensation arises when, unlike the contributors to "Our little trips down memory lane", we are unable to identify exactly what it is we are recalling when pricked by a smell or a taste.
Frederick Raphael's piece and the accompanying recollections bring to mind Edward Thomas's poem "Old Man" (referring to the pungent herb also known as lad's love and southernwood), in which he writes of having "mislaid the key":
"I, too, often shrivel the grey shreds,
Sniff then and think and sniff again and try
Once more to think what it is I am remembering,
Always in vain..."
and is left with "Only an avenue, dark, nameless, without end".