On the skids: a brief history of the shopping trolley: A rogue machine, injuring thousands, is in your shops now, says Hester Matthewman

'A TROLLEY is a highly complex piece of equipment with huge dichotomies pulling it in different directions,' according to Donald Macdonald, Group Sales and Marketing Director for Clares Equipment Group, a leading wire-goods manufacturer. The company has made supermarket trolleys for more than 20 years. Being a trolley expert has certain disadvantages: 'At dinner parties, people are always onto you like a dose of salts with all sorts of complaints. There are so many different priorities which all have to be considered that people don't think of - safety, stability, capacity, maintenance, ergonomics, fitting through the checkout.'

Trolley design is a serious business. Another trolley manufacturer refused to say anything at all about his company's latest technical refinements, on the grounds that trolleys were often the subject of undue hilarity. 'It's not a topic that can be dealt with briefly, and it's not a humorous subject. I'm not prepared to talk to you,' he snapped.

The trolley was invented in 1937 by Oklahoma supermarket owner Sylvan Goldman. Known as the 'shopping cart' in the United States, it evolved from the wire hand-basket, when Goldman noticed that his customers stopped buying as their full baskets became too heavy to carry. As self-service shopping caught on, his trolleys became so popular that he had a seven-year waiting list for delivery by the end of the decade.

Fifty years later, Gene von Stein, vice-president of the US shopping-cart giant Unarco Commercial Products, hailed the trolley as 'a complex sociological phenomenon that has totally changed the commerce and culture of America and the world.' American trolleys can now be fitted with calculators and electronic store guides.

British shoppers made do with a primitive wooden frame on wheels that could support two baskets, until the shopping trolley arrived in the UK in 1950 at Sainsbury in Croydon. Since then, trolleys have changed very little.

American manufacturers have partially solved the perennial trolley- with-a-mind-of-its own problem, by fixing the two back wheels to keep their carts on the straight and narrow. However, this means that American shoppers have to keep strictly on track as they move round the shelves. According to Donald Macdonald, such a disciplined approach would not suit the impulsive British shopper. 'Have you ever pushed a trolley with fixed wheels at the front or rear? You can go in a straight line but you can't move sideways or get out of other people's way. If you want to fill your trolley with the pet-food that's across the way you can't do it. There are a lot of problems involved with going in a straight line.'

An average-sized supermarket has a fleet of around 250 trolleys, each costing 'up to pounds 72' to replace, and 15 to 25 per cent of supermarket rolling stock disappears every year.

One exasperated supermarket did eventually get a prosecution for stealing a trolley as far as crown court, only to have the case dismissed on a technicality. Because the woman concerned had put a pound in a coin slot to detach the trolley, she was deemed to have entered into a contract with the supermarket, despite the fact that when the judge asked her 'When did you gain possession of the trolley?' She replied: 'When I nicked it'.

As a report revealed last week, 7,500 unwary victims were hospitalised last year after tangling with shopping trolleys. Injuries ranged from fractures, concussion and bumped heads to severe bruising of shins and ankles. And this could be only the tip of the iceberg, warns a spokesman from the Royal Society for the Prevention of Accidents (RoSPA). 'Loads of people who get slight bruising, but still enough to hurt them, just don't bother to go to hospital.'

RoSPA admits that safety problems often come down to the user rather than the design of the trolley. 'Many trolley accidents are caused by people quite blatantly messing about. For instance, they use them as scooters.'

The new Health and Safety Executive guidelines on shopping trolleys recommend leaflets with the slogan 'Look out, there's a trolley about]' to highlight in-store dangers, and a spokesman offered the following advice to intrepid supermarket-goers: 'Be very aware of your surroundings. Don't go into the supermarket in a daze. You need to have your wits about you]'

RoSPA also hopes public-spirited shoppers will help to root out rogue trollies. 'If you start moving your trolley around and it's not going the way it should, ie forward, we would urge members of the public to make the situation known to the store management straightaway. They should be only too pleased to find you a replacement.'

(Photograph omitted)