Although obvious now, the rearview mirror wasn't really invented until the 1920s. Even then, it was mostly used for driving fast and avoiding the police. If Edmund Bentley is remembered for anything these days, it is probably for the creation of the whimsical, four-line biographical poem with an AABB rhyming scheme which bears his middle name, Clerihew.
However, he also wrote Trent’s Last Case (1913), which, in the opinion of Agatha Christie, was ‘one of the three best detective stories ever written’, while for Dorothy L Sayers ‘it shook the little world of the mystery novel like a revolution...
Every detective writer of today owes something, consciously or unconsciously, to its liberating and inspiring influence’. From the modern perspective, one of the story’s curiosities is that the plot turns on a glance into a rear-view mirror of a car. From the context it is clear that what is now commonplace feature of a motor vehicle was anything but and was the sort of state of the art piece of equipment that might appeal to a plutocrat like Manderson.
The irony, of course, is that it leads to his undoing. At the time, many motoring enthusiasts had trouble enough getting to grips with their vehicle and driving forwards without worrying about what was happening behind them. Anyone who felt the need to look behind had either to turn their own head, a dangerous manoeuvre as it diverted their attention from the road, or get a passenger to act as a lookout, or bring their own m.