The Art of projection and complete magic lantern ... - Yesterday Image

THE PAMPHENGOS LAMP.It is imagined by many that the Pamphengos flames to burn at theirbest should rise up solid and even, as in the case of an ordinary tablelamp ; also that the flames should be of an equal height in burning.Whereas, practically, this must not be with the Pamphengos because ofits perfect combustion and whiteness of light, and this only can be obtainedunder certain conditions, which is by admitting the proper quantityof air through the perforations under the cone, the flames necessarilyburn in a forked or zigzag manner. This is exactly what is required, asby this arrangement the flames are made white and dazzling.The only portion of the flame that is of any optical importance, andalone taken up by the condenser is that portion dotted in the illustration.The points offlame above andthe portions below are useless.lll^^^^^^HI -^'S- ^'^^^The condenser only taking upthose central rays. If theflames were required to comeup solid and even, as a gasburner,more oxygen wouldbe needed, this can be illustratedby raising the hood oflamp whilst burning,the flamesare then seen to run up,but are feeble and yellow,with a tendency to smoke.The flames when at theirfullest should reach up thechimney as shown in fig. 12B.There is a point beyond which the flames cannot be turned without theirdropping down, and care is required not to turn them beyond that point.Fig.12BFig. I2B shows a section of the lamp, as seen at the back,with flames at their full height (just entering the chimney.)Notice also that the wicks are some little distance out ofthe wick tubes, although the wick is only alight at the top,more especially the two sides. As every lamp is testedbefore being sent out, it is perfectly certain that everynovice can obtain the best results, providing, of course,that the instructions are properly carried out. Use onlyfresh and good oil and wicks that have been welldried ; and RE cut every time before using in aperfectly straight line thus, '— » with the corners cut off;and by no means cut thus ^^. If, perchance, the oil orwicks should be bad, or other occasions arise, the littlerack and pinion shown at the side of the lamp will raisethe hood and admit more air, which will cause the flameto run up and heat the chimney, when this is brought about the hoodmay again be lowered ; this should only be used when absolutelynecessary.