32 SCIOPTICON MANUAL. 



common lump. E" is level, to allow the lamp (the wicks being 

 turned down) to slide in and out. E slopes so as not to shade tho 

 light from the condenser. 



F Narrow strip of glass, quarter of an inch wide, held in a 

 socket before the flame, to give upward direction to heated air. It 

 will not crack from heat because it is so narrow, and without ob- 

 structing light it takes from tho glass G its liability to crack. 



O Front of flame-chamber glass It is now held in a tin frame 

 by a wire ring, so that should it crack, it is still kept in place with- 

 out harming the effect on the screen. 



G' Back flame-chamber glass. The lamp is lighted by remov- 

 ing this glass, and reaching the wicks with a lighted match. G G / 

 must be in place to secure the draft. F, especially since the intro- 

 duction of the tin frame for <?, is scarcely necessary. 



H Reflector, used also to close the rear of the cylinder. The 

 centre of concavity is at JEX, so that reflected rays are thus made to 

 coincide with incident rays from E / to the condenser. 



7 Chimney, giving large outlet to heated air. 



J Chimney cap, for darkening the outlet. It may be raised to 

 increase the draft, when the lamp gets to burning freely enough to 

 bear it. 



PACKING. 



No instrument is forwarded without being first proved 

 by careful trial. The oil is then poured off, and the 

 lamp burned awhile afterwards, to prevent any further 

 drainage should it be shipped wrong side up. Let this 

 precaution be taken by all who pack the instrument for 

 transportation, that there may be none of the offensive 

 smell of oil when the instrument is unpacked and used. 



The wicks are left in the tubes, ready for use. Four 

 extra wicks, with the narrow glass, J?, are tied together, 

 which with a dozen flame-chamber glasses, Gr Gr f , are 

 sent with each instrument. F is removed, as it is liable 

 to fall out if inverted. For the most part Gr G' are left 

 in place. Packing is placed between G and </, to pro- 



