One of the more dubious attractions on Brighton’s Palace Pier back in the 1960s – the Swinging Sixties – was the row of What the Butler Saw machines in the amusement arcade. It’s the theft of a film from a What the Butler Saw machine on Palace Pier which sets my fictional journalist Colin Crampton off on his most dangerous adventure yet in Stop Press Murder.

  For those too young to remember, What the Butler Saw machines were metal contraptions on spindly legs. The main part consisted of a cylindrical drum with a handle and a viewer. You put a penny in a slot, cranked a handle and watched a film through the viewer.

  The film was invariably a silent movie which showed a young woman with a clothing difficulty. The difficulty being that she didn’t have her clothes on. By today’s standards, it was tame stuff, but still considered racy – even in a decade when men were growing their hair longer than ever and women were cutting theirs shorter.

  The What the Butler Saw mechanism had actually been invented in 1894 by an American called Herman Casler. He called it a mutoscope. Unlike a conventional role of film, the machine contained a giant flip-book – a kind of huge Rolodex. A central reel held around 850 cards, each with a photograph. As you cranked the handle, the machine flipped the cards to create a jerky moving picture.

  Casler’s original advertisement for the machine envisaged cultured ladies watching improving topics, such as scenes from Shakespeare’s plays. But his dream didn’t turn out quite like that. And the porn merchants of their day soon realised mutoscopes could be ideal for showing naughty films that couldn’t be displayed in cinemas (or bioscopes as they called them then). One of Casler’s machines ended up as a star attraction in the men’s lavatory on Rhyl pier in north Wales.

  In 1899, Disgusted of Tunbridge Wells penned a letter to The Times to condemn their “vicious demoralising picture shows”. Added Disgusted: “It is hardly possible to exaggerate the corruption of the young that comes from exhibiting, under a strong light, nude female figures as living and moving, going into and out of baths, sitting as artists’ models, etc.”

  Evidently, however, punters were paying their pennies and lapping it up. One contemporary report mentioned a film called “Birth of the Pearl” which had been partly damaged. The picture cards which had become most creased were those showing “full frontal nudity”. Ahem!

  So, how did Casler’s scientific name of mutoscope get dumped in favour of What the Butler Saw? This dates from a sensational divorce case in 1884 between Lord Colin Campbell, a son of the Duke or Argyll, and his wife Gertrude, a celebrated beauty of the age. As the case developed, it turned dirty with each making allegations against the other.

  Campbell claimed that Gertrude had been carrying on with a string of men, including Captain Sir Eyre Shaw, the head of the London fire brigade. To back up his case, Campbell brought in his butler who claimed to have watched Gertrude’s love-making with different men through the keyhole of her bedroom.

  The issue became so heated that the judge adjourned the trial to the Campbell’s London house so that jury members could peer through the keyhole themselves and decide just how much the butler could have really seen. The phrase “what the butler saw” was used widely in newspapers – and has stuck ever since.