lower amplitude effective voltage applied to that tungsten filament to increase the produced light intensity of course the resistance of the resistor 30 is then adjusted in relation to the electric resistance of the tungsten filament of higher power rating fig4 of the appended drawings illustrates an incandescent lamp of ps line type generally identified by the reference 50 like the above described a line type lamp 10 the ps line type lamp 50 comprises an envelope 51 made of soft or hard glass and formed with a bulb portion 52 a neck portion 53 a flare 54 itself defining a cavity 55 and an exhaust tube 57 extending outside the envelope 51 through the cavity 55 from the bottom 56 of this cavity 55 a stem press 58 a stem 59 arbour and a button 60 successively and axially extending from the bottom 56 of the cavity 55 inside the glass envelope 51 to form a one piece glass support a coil or coiled coil filament 62 made for example of tungsten one to five five in the illustrated example metallic wire supports such as 61 each having a first end embedded in the glass material of the button 60 and a second end supporting the tungsten filament 62 a first cylindrical metal base 63 having one end conventionally secured to the distal end of the neck portion 53.