Memories, both fond and otherwise, can be recalled by the least expected of external stimuli. A snatch of conversation, the scent of a Spring blossom, a few bars of a tune long since in vogue. Many things. So it was last week whilst queued-up in suffocating heat, waiting to board the Chunnel train back to Britain last summer, that my glance fell upon one of the uniformed young women directing cars aboard the upper deck of...