the th LK life of au an incandescent lamp from the consumers point of view viah one of the chief charges that can be 16 brought against the incandescent electric light 1 is the fact that its iti efficiency falls off with use at the electrical laboratory of the ohio state university a prolonged inquiry ha has been conducted into the life and efficiency of the incandescent lamps of ten different american makers the results result show how that the mean candle power falls falli off with use approximately at the rate of 10 per cent for each hours that the th life of 96 out of lamps exceeded hours and i that the average initial efficiency wu was ta 2 after hours 56 and after 1200 hours 7 waltg per candle power pitt fitte burg dispatch