Show makes make powerful light adding a minute part of a rare metal rubidium to mercury usually used in mercury lamps has resulted in tile development ofa of a lamp whose light approximates sunlight the metal causes the alio lamp to give red ra rays yo tit in addition to the mercury spectrum tile the lamp Is said to have a life ten times as long as an ordinary incandescent lamp rubidium illum costs 7 a dram drain but only ono one efte hundredths part of tho the metal Is 19 used in each lamp to change the lie light hue front from green to light red previously had improved the mercury lamp by addla potassium to tile the mercury but the potassium la Is said to disintegrate tho the glass bulb or tubo tube of tho the lamp popular mechanics magazine |