Mr. Ainger on the Illumination of Theatres* 47 



flames may be supplied with a steady current of pure air ; they 

 will therefore burn with little smoke, and neither air nor smoke 

 will ever in any way become obnoxious to the audience. The 

 house may thus be preserved well ventilated and clean, while 

 the lights, by their perfect combustion, will be rendered eco- 

 nomical, and still more so by the opportunity of using appro- 

 priate reflectors to direct the rays towards the points at which 

 they are required. It is not an exaggeration to say that four- 

 fifths of the light at present employed are wasted in conse- 

 quence of radiation in worse than useless directions, or of 

 absorption (to use the common term) by imperfectly reflecting 

 surfaces. 



I propose to remove the foot-lamps and the central chande- 

 lier, together with all the smaller lights round the circumference 

 of the house, and to substitute an illuminated dome, as shown 

 (in the plate) in section, fig. 1, and in plan, fig. 2. This dome 

 would, at its lower part, be formed into circular or octagonal 

 panels, the frames of which might be enriched and gilt, but the 

 panels themselves would be occupied by glass, behind which 

 would be lights of greater or less power, and to each a reflector 

 equal in diameter to the panel, and of greater or less perfec- 

 tion in regard both to form and materials. 



In the drawing I have described three tiers of circular 

 panels, each containing thirty-six, or in the whole one hundred 

 and eight. To the quadrant immediately opposite the stage, 

 or from C to C in figure 2, containing twenty-seven panels, I 

 should apply the most powerful gas-lights* I could obtain, 

 and the most perfect parabolic reflectors. Their axes would 

 be in radii of the dome, which would be made such a segment 

 of a sphere, that those radii would point precisely to those 

 parts of the stage where the light was required. It may be 

 thought that light so directed would be too concentrated, or, 

 in the language of artists, spotty ; but as the reflectors would 

 not average more than eighteen inches in diameter, and the 

 flames would have considerable magnitude, so much of the 

 source of light would be ex-focal, that each parabola would 

 supply a cone of rays sufficiently obtuse to mingle with those 



* If it be desirable to employ the light of lime burning in oxy-hydrogen gas, 

 such an arrangement us is here proposed seems peculiarly adapted to the purpose. 



