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Armco
The metal safety barriers that line roads, usually motorways or at dangerous bends, are designed to stop a car from leaving the road or crossing a central reservation, without deflecting it back into the traffic again, and to deform in a way least likely to cause it, and its occupants, damage.
Usually made from steel, Armco isn't strictly the name for these safety barriers, but this has become a generic term referring to the American company which made most of them.
The use of such barriers dates back to the 50s, but they came most widely to public attention in the early 70s as a safety device in motor racing. Fitted around many Grand Prix, Indy and NASCAR circuits, among others, in response to the horrific fatality rate, they initially attracted much controversy, especially at venues such as Watkins Glen, where the 'soft wall' met with much opposition and strikes by drivers, and the Zaandvoort GP circuit near Amsterdam, which closed after a death was attributed to the collapse of the Armco barrier. Refined and further developed, Armco is now near-universal at racing circuits and is credited with saving many lives.
However, it has been on the roads where it has had the most positive impact and although new 'stepped' concrete walls are now taking its place (ie down the centre of many motorways), Armco remains cheap and effective.
The metal safety barriers that line roads, usually motorways or at dangerous bends, are designed to stop a car from leaving the road or crossing a central reservation, without deflecting it back into the traffic again, and to deform in a way least likely to cause it, and its occupants, damage.
Usually made from steel, Armco isn't strictly the name for these safety barriers, but this has become a generic term referring to the American company which made most of them.
The use of such barriers dates back to the 50s, but they came most widely to public attention in the early 70s as a safety device in motor racing. Fitted around many Grand Prix, Indy and NASCAR circuits, among others, in response to the horrific fatality rate, they initially attracted much controversy, especially at venues such as Watkins Glen, where the 'soft wall' met with much opposition and strikes by drivers, and the Zaandvoort GP circuit near Amsterdam, which closed after a death was attributed to the collapse of the Armco barrier. Refined and further developed, Armco is now near-universal at racing circuits and is credited with saving many lives.
However, it has been on the roads where it has had the most positive impact and although new 'stepped' concrete walls are now taking its place (ie down the centre of many motorways), Armco remains cheap and effective.
Cats' eyes
One night, a road-mender from Yorkshire was driving home and swerved to avoid a cat – which he noticed because its eyes had reflected his headlamps. If Percy Shaw hadn't seen that cat's eyes, he would have driven straight over a precipice. He went on to develop one of the simplest, but most effective, road safety devices: a road stud with 'retroreflectors' that send a beam of light back on a parallel path to the ray that enters, just as the retina of a real cat's eye works.
Shaw's glass studs were maintenance-free and even incorporated a self-cleaning method using rainwater, inspired by tear glands and eyelids. He patented the design in 1933, the first 50 were fitted to a road in Bradford and he went on to become a millionaire and OBE.
Most cats' eyes on British roads today are white and are positioned down the centre of a road; red cats' eyes mark out a motorway hard shoulder; amber denotes the central reservation; green are for a junction; and mark out blue for designated police sliproads.
Modern solar-powered LED road studs are now making their debut, but are more expensive to make and may not last so long.
One night, a road-mender from Yorkshire was driving home and swerved to avoid a cat – which he noticed because its eyes had reflected his headlamps. If Percy Shaw hadn't seen that cat's eyes, he would have driven straight over a precipice. He went on to develop one of the simplest, but most effective, road safety devices: a road stud with 'retroreflectors' that send a beam of light back on a parallel path to the ray that enters, just as the retina of a real cat's eye works.
Shaw's glass studs were maintenance-free and even incorporated a self-cleaning method using rainwater, inspired by tear glands and eyelids. He patented the design in 1933, the first 50 were fitted to a road in Bradford and he went on to become a millionaire and OBE.
Most cats' eyes on British roads today are white and are positioned down the centre of a road; red cats' eyes mark out a motorway hard shoulder; amber denotes the central reservation; green are for a junction; and mark out blue for designated police sliproads.
Modern solar-powered LED road studs are now making their debut, but are more expensive to make and may not last so long.
Road cones
Ubiquitous adornments to our roads, usually signalling that a lane is closed for roadworks... even if there's not a hole or a labourer in sight.
Endless queues of red and white plastic 'witches' hats' sit on our motorways in malevolent lines. But you have to admit they do an effective job: clearly visible, easy to move around and put in position, adaptable and versatile, cones must have saved the lives of many roadworkers as well as successfully and safely diverting traffic. The design dates back to 1914, although early cones were concrete.
Cones will also go down in history as a symbol of John Major's Conservative government; greater global problems not withstanding, Major introduced his Road User's Charter in 1992, known as the Cones Hotline. This aimed to speed up progress along Britain's congested roads by inviting drivers to report unnecessary lane closures and so on, but was quietly dropped a few years later. It's one of the more memorable issues of the Major years.
Ubiquitous adornments to our roads, usually signalling that a lane is closed for roadworks... even if there's not a hole or a labourer in sight.
Endless queues of red and white plastic 'witches' hats' sit on our motorways in malevolent lines. But you have to admit they do an effective job: clearly visible, easy to move around and put in position, adaptable and versatile, cones must have saved the lives of many roadworkers as well as successfully and safely diverting traffic. The design dates back to 1914, although early cones were concrete.
Cones will also go down in history as a symbol of John Major's Conservative government; greater global problems not withstanding, Major introduced his Road User's Charter in 1992, known as the Cones Hotline. This aimed to speed up progress along Britain's congested roads by inviting drivers to report unnecessary lane closures and so on, but was quietly dropped a few years later. It's one of the more memorable issues of the Major years.
Road salt
And whose great idea was that? Spreading a highly corrosive substance on the roads in the winter that could render a poorly-rust-proofed car riddled with holes by springtime? And one which has the noxious side-effect of killing roadside vegetation, contaminating ground-water and altering the chemical balance of nearby lakes and rivers?
But we've got to keep the roads open in icy and snowy conditions, and salting or gritting the roads has been estimated to save five or six lives each icy night, according to one European study, and reduce accident rates by nearly 90% in some northern US states.
Rock salt, sometimes mixed with a little sand or gravel to form a grit, lowers the temperature at which water freezes, limits the formation of ice on a road surface and stops snow from settling, as long as you get it sprayed on the roads before the snowstorm comes.
Each winter, our Highways Agency makes proud pronouncements about the number of gritters it has on standby. You'll need to wash the residue off your car's bodypanels, and from its underside, on a regular basis to avoid corrosion, though modern-day galvanized chassis are at least more rust-resistant.
And whose great idea was that? Spreading a highly corrosive substance on the roads in the winter that could render a poorly-rust-proofed car riddled with holes by springtime? And one which has the noxious side-effect of killing roadside vegetation, contaminating ground-water and altering the chemical balance of nearby lakes and rivers?
But we've got to keep the roads open in icy and snowy conditions, and salting or gritting the roads has been estimated to save five or six lives each icy night, according to one European study, and reduce accident rates by nearly 90% in some northern US states.
Rock salt, sometimes mixed with a little sand or gravel to form a grit, lowers the temperature at which water freezes, limits the formation of ice on a road surface and stops snow from settling, as long as you get it sprayed on the roads before the snowstorm comes.
Each winter, our Highways Agency makes proud pronouncements about the number of gritters it has on standby. You'll need to wash the residue off your car's bodypanels, and from its underside, on a regular basis to avoid corrosion, though modern-day galvanized chassis are at least more rust-resistant.
Tarmac
John Loudon MacAdam of Ayr, Scotland, developed a method of surfacing tracks back at the end of the 18th century; 'macadamising' was the putting down of a compacted layer of crushed gravel and sand, sprayed with water. This enabled horses and carriages to travel well-worn routes, previously dirt tracks, without churning them up in the wet or creating dust-storms in the dry – and was far, far cheaper than noisy, slippery stone paving slabs or cobbles.
It wasn't strong enough to cope with motorised cars, however. English businessman E Purnell Hooley made a lucky accidental discovery in 1901, seeing a barrel of coal tar spilt on a macadamised road. Gravel was put on the tar to cover it and the resulting surface was almost dust-free to drive over. He patented the idea, called it (logically enough) Tarmacadam, and the modern road was born.
These days, tarmac (or 'blacktop', as the Americans call it) has been largely superseded by stronger asphalt – less sensitive to heat and more resistant to erosion – or modern forms of concrete, but it was tarmac that literally laid the road for motoring.
John Loudon MacAdam of Ayr, Scotland, developed a method of surfacing tracks back at the end of the 18th century; 'macadamising' was the putting down of a compacted layer of crushed gravel and sand, sprayed with water. This enabled horses and carriages to travel well-worn routes, previously dirt tracks, without churning them up in the wet or creating dust-storms in the dry – and was far, far cheaper than noisy, slippery stone paving slabs or cobbles.
It wasn't strong enough to cope with motorised cars, however. English businessman E Purnell Hooley made a lucky accidental discovery in 1901, seeing a barrel of coal tar spilt on a macadamised road. Gravel was put on the tar to cover it and the resulting surface was almost dust-free to drive over. He patented the idea, called it (logically enough) Tarmacadam, and the modern road was born.
These days, tarmac (or 'blacktop', as the Americans call it) has been largely superseded by stronger asphalt – less sensitive to heat and more resistant to erosion – or modern forms of concrete, but it was tarmac that literally laid the road for motoring.
