THE AIR cooler is a fascinating gadget that I've discovered in Delhi. The ugly-looking but effective apparatus is a savior during the city's sizzling dry summer. Water is filled inside, and a small motor pumps it up to flow on the sides. A powerful fan forces the water to evaporate, thus cooling the atmosphere indoors. With one drop of essential aromatic oil on the inner water tank, the evaporative water fills the air with a breezy scent. This wonderful invention beats the power-guzzling air conditioner by a mile.