400, 250, AND 85 WATTSCD 1964050 E&MP27.008 Electric Lighting 1937 Three commercial types of high intensity mercury vapor lamps. Left: double bulb, 400 watt, 16,000 lumens. Middle: 250 watt, single bulb, 7500 lumens. Right: double bulb, 85 watt, 300 lumens.
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