MOBS are bad for businesses—unless you are selling riot-control gear, that is. Even before this week’s riots in Britain governments were bracing themselves against protests stoked by the economic downturn. Firms such as Israel’s Hagor Industries are doing a roaring trade in antiriot shields, batons and helmets. David Frenkel, the firm’s production manager, says demand is growing from police and military services in Europe, South America and Africa, bolstered by “war, unrest and natural disasters”. Ochlocracy—mob rule—was a term coined in ancient times, when grain prices or a celebrity murder could spark a riot. The Roman emperors’ Praetorian Guard used cavalry and swords against stone-throwers. Their latter-day counterparts (human and equine) are better protected, with goggles, shields and other kit made of lightweight, flameresistant, unshatterable and stab-proof materials. They also have more ways of disrupting the rioters. Police in India spray unruly crowds with coloured water: stained and sodden agitators are easier to identify. America’s forces have developed (but not used) a “heat ray” designed to clear crowds by painfully zapping the skin. The unfamiliar tones of classical music can disperse loiterers, while big sound-blasters, known as “long-range acoustic devices” (LRADS), have been deployed against protesters in some American states. At a cost of up to $30,000 they can emit sound at 150-plus decibels (like a roaring jet engine at close range). Israel has a fancier version known as the “Scream” that affects the inner ear and induces nausea. When ochlophonics fail, authorities there have been known to douse Palestinian protesters with “skunk bombs” of smelly liquid. Eyes are as vulnerable as ears and noses. A firm called Intelligent Optical Systems, based in California, is developing, with government backing, a strobe torch that makes targets dizzy and disoriented (at least within a range of 15 metres). Laser Energetics, in New Jersey, sells “Dazer Lasers” that emit a green beam capable of dazzling people up to 2.4 km away.

(Aug 13th 2011 | www.economist.com)

The underlined pronoun ‘they’ in ‘At a cost of up to $ 30,000 they can emit sound at 150-plus decibels.’, refers to: