Click here to print this page

Planning Retirement Online

Raise a cup and be thankful


Raise a cup and be thankful  

Sandra Lawrence researches the history and progress of a familiar product found in every home  

I’m perched on an upturned bucket, surveying three slightly uneven rows of freshly-planted potatoes and sipping piping-hot coffee poured from a direct descendent of Snr. Torricelli. Never heard of him? You may not know it (though you are about to find out), but you have reason to be extremely grateful to the guy.

As does 92 year-old fellow allotment-holder Tom, who raises a steaming mug, his trusty Thermos at his feet. And his mate Alf who is packing his flask into his barrow and heading off home for lunch.  


I am, of course, talking about the vacuum flask, invented by accident in 1643 by Evangelista Torricelli, when he was trying to build the world’s first barometer, having previously created the world’s first vacuum.  

Torricelli did not invent the vacuum flask itself. It’s the concept that was his.  In fact, the vacuum flask has been around for a hundred years, invented by Cambridge scientist Sir James Dewer in 1892 and patented in 1903 as the “Dewer Flask.”. The name was the result of a competition held in Germany to come up with a title. The product had been adopted by two German glassblowers who eventually awarded the prize to a Munich resident who suggested “Thermos” from the Greek word “Therme” meaning “hot.”  

Since that time the vacuum flask has gone from lifesaver in WWI trenches to style icon not out of place in an executive briefcase. Thermos flasks were an immediate success. In an age when discovery was the watchword, no expedition was complete without a Thermos. Shackleton took one with him to the South Pole, whilst at the other end of the earth Robert E. Peary was enjoying his flask in the Arctic . The Wright brothers carried one in their aeroplane and Count Von Zeppelin’s flying machine included a Thermos too.  

Memories of childhood picnics, days out to the seaside and school lunch boxes jostle with visions of builders’ tea breaks and shivering anglers at the very mention of Thermos – a brand name that has become virtually generic.  

“We have 99% brand awareness,” says Paul Johnson, Thermos’ business development manager. “Even the French, who are notorious for keeping their own language, call the vacuum flask ‘le Thermos’.”  

Vacuum flasks are simple enough in concept. The best way to stop heat transfer is to create a barrier between contents and outside world. Foam insulation will work for a while, but a vacuum cannot transfer anything, thus preventing conduction and convection. The silvering on the glass inside a flask (or the polished steel on the trendy new ones) reduces infrared radiation.  

In the quest to balance vacuum and practicality, traditional bugbears of weight and volume have seen the lining and casing becoming smaller and thinner allowing greater capacities inside. In 1928 double-walled Pyrex® glass was used to create a twenty-eight gallon monster, popular with ice cream parlours and fishmongers.  

But it is with domestic users that the humble vacuum flask has found its niche. From the introduction of the pint-sized “Blue Bottle” in the early 1920s, it has found a place in the heart of every secretary, builder’s mate and film star – W.C. Fields famously sipped martinis from his.  

Styles have changed – my family had a tartan one in the sixties, a charming tin-cased affair topped with a cream plastic lid doubling as a cup. Handles came slightly later, along with funky 70s flowers and geometric patterns – examples of which change hands in antique markets today for around £20.  

For the last twenty years or so, moulded plastic with a silvered glass interior has been the standard. “It’s like an old mate,” says Derek Murphy, patting his green plastic moulded Thermos which has accompanied him to building sites all over the South East for the last seven years. “It comes with me wherever I go and is more faithful than my dog.” Somewhat less faithful himself, Derek has his eye on one of the new stainless steel varieties.  

There’s definitely a swing towards the brushed steel “bullet” styles,” says Paul Johnson. “It’s not entirely due to aesthetic reasons  though – they are safer, have better heat retention and now that steel prices are tumbling they are cheaper too.”

Sara Davey, buying manager at the Cookshop in Selfridges in London has also noticed the huge increase in sales in stainless steel this year. She says. “We stock two kinds – Thermos and Elia, and our top sellers in each brand are stainless steel. This year I’m introducing a Light and Compact from Thermos which is in a rather nice powder-blue steel and meant for people who are out and about. Then I’m going to the other extreme with the “work” series. They’re tough. They look very traditional – the whole retro thing is very big just now. There’s one called “The Rock” which keeps liquid hot for up to 24 hours.”  

Internet survival guru Kurt Saxon claims that an entire family’s cookery can be done using vacuum flasks. “Save on wood, weight of food carried, and food odours to alert bears or enemies,” he enthuses, cheerily advising how to create 1½lbs of “dessert” for 46 cents. More discerning web surfers might prefer to investigate offering a titanium version for a mere $129.  

Vacuum flasks have carried everything from rare tropical fish to blood, bones and insulin, in ‘planes at high altitudes. But by far the most popular contents are tea and coffee. Some complain that flasks impair the taste, but John Rickaby of specialty coffee company Café Origin disagrees. “Obviously fresh coffee is preferable,” he says, “but whereas a traditional hotplate will just “stew” coffee, a good quality vacuum flask will slow the rate of deterioration.” Chris Wright, from tea merchants London Cuppa has other ideas. “The best way is to bring the hot water in the  flask and  then make the tea on the spot – it’s not hard to bring a few teabags. And carry milk in a separate container. ”  

But what of Evangelista Torricelli’s invention? Well, he suffered for his service to flask-kind. The Renaissance Church declared that since God was omnipresent there could be no such thing as a vacuum. Torricelli was declared a heretic and ultimately buried in an unmarked grave.

A version of this article first appeared in the Times newspaper    


laterlife interest

The above article is part of the features section of called laterlife interest. laterlife interest contains a variety of articles of interest for visitors to written by a number of experienced and new journalists.

It includes both one off articles and also regular columns of a more specialist nature such as healthwise, reports from the REACH files, and a beauty section called looking good in later life.

Also don't forget to take a look at our regular IT question and answer section called YoucandoIT by IT trainer and author Jackie Sherman.

To view the latest articles and indexes to previous articles click on laterlife interest here or above.  To search for articles about a certain topic, use the site search feature below.



back to laterlife interest

Site map and site search


Advertise on

LaterLife Travel Insurance in Association with Avanti