A marvel of 1930s cocktail technology

The Rapid patent cocktail mixer from 1933. You can see it in action in the video below

Drifting through my local flea market (sorry, “Antiques & Collectibles Fair”) my eye was caught by a strange device. It looked a bit like a cocktail shaker with a glass body, silver-plated cap and integral spout, but protruding from the top was a plunger or piston. Closer inspection revealed that it was not for shaking—instead there was a spinning paddle inside, driven by pumping on the button on the top. It was an automatic cocktail stirrer.

Drawings from Rolph's patent application

To shake or to stir? Most cocktails require chilling and while some are constructed around ice cubes that stay in the drink, many are chilled through brief and vigorous exposure to ice before being strained and served ice-free, to avoid unfortunate and unpredictable dilution as the ice melts. You can do this most flamboyantly and speedily by putting the drink and the ice in a shaker and shaking it hard. But this will break up the ice a bit, leaving little shards of it in the cocktail (which bar pros tend to strain out by pouring the finished beverage through a device a bit like a tea strainer) and a cloudy finish that bothers some people—though to be honest the cloudiness fades quickly. (Japanese bar legend Kazuo Uyeda, on the other hand, seems to like these bits of ice: not only does he use a Manhattan shaker without a strainer, but he up-ends the shaker and gives it a good waggle to chase out any ice shards that might be lurking inside.)

But others are so concerned about ice contamination that they won’t shake certain cocktails at all, preferring to stir them over ice. This way your drinks stays clear and dilution is kept to a minimum. Many consider that certain drinks like a Martini will be “bruised” if shaken—the entrenchedness of this idea is precisely why James Bond bucks the trend and insists his Martinis are shaken.

The machine in the market had clearly been designed to enable drinks to be stirred but in a low-effort and thoroughly modern way. I immediately made it clear to Mrs H. that this would be a highly suitable thing to buy me for Christmas.

An earlier patent of Rolph's, for a "radiator cap
ornament". That's pretty much all it says, though it
looks to me as if the head and hands bob up and down

In time I discovered that it was an invention called The Rapid. It was the brainchild of one William Mair Rolph, who patented it in 1933. There isn’t much about Rolph online, though he was clearly a serial inventor—as well as pumps, syringes, devices for the accurate measurement of doses of liquid and a picnic hamper that unfolds into a table, he came up with many improvements for motor cars, such as indicators, windscreen wipers, a sun visor for the driver, and—bizarrest of all—a radiator cap ornament in the form of a seated Chinese figure which, according to the patent documents, really is nothing but an ornament. Aside from that I gleaned that he was inducted into the Royal Aero Club in 1914 and in 1917 was decorated by the King of Belgium for his contributions during the Great War. (I like to imagine he was in the Royal Flying Corps but I have no evidence for this. He may have been a spy, for all I know.)

I’ve seen various configurations of the Rapid design online, including one which is all metal. The patent application suggests it should have gradations marked up the side to help mixing, but whoever made mine clearly decided to go with the vertical cut-glass fluting for aesthetic reasons instead. The patent document also shows an alternative paddle with fork-like prongs for beating eggs, cream, etc. But the point is that this was not just a pipe dream—these things were actually manufactured.

So does the Rapid work? It’s more fiddly to load and clean that a bar glass or beaker but, as you can see from the video below, that paddle really does swoosh the ice and liquid around. For any given length of time spent mixing, the Rapid delivers more cooling than a human arm and a barspoon, yet the resultant liquid is perfectly limpid and seems not to taste any more diluted.

However, I did discover that my particular example has a tendency to jam. (In fact you can see in the video that at the end of the mixing, just before I pour it, it does precisely this.) But when it’s working it does a good job. Needless to say there are electric drink mixers out there now, but nothing as stylish as this.