The daily morning journal and courier., 1907-05-31
LIGHTING ENGINEER.
His Field Extends With Growing Use
  of Electricity.

One of the most interesting profess sions to which modern progress in electrical science has given rise is that of the lighting engineer Before the era of electricity the work of the light ing expert consisted chiefly in deter mining the number and size of the va
 rious rooms to be lighted and approx inately the number of feet of cast iron gas pipe required in the, several sizes, which gradually diminished according to fixed rules, from the street main to the last jet at the top of the building. The fixtures were most frequently fur nished from stock designs, and select- cd to conform to a more or less shrewd guess at the lighting requirements. A guess, with a generous allowance for error, was about the best that could be done in this latter respect, in view of the uncertain pressure on the mains and the varying efficiency of gas as an iliuminant.
 With the advent of electricity, how ever, all this has been changed, for electrical fixtures lend themselves much more freely to artistic designing, just as the more constant illuminating value of the electric current makes it possible to determine with practical accuracy the degree of illumination tha, will be afforded by certain num- Der of lights of given candle power. There are stock designs in electrical
 fixtures, of course, just as there have been stock designs in gas fixtures ever since the history of gas as an illum- inant began, and enormous quantities of them are used every year in the more ordinary classes of work
 But the brass, bronze and iron east ings and stampings which make up the lighting fixtures of commerce af- ford such narrow margin of profit that every manufacturer who aspires higher than a bankruptcy court finds It necessary to employ, at salaries run ming well up into four figures, experts whose business it is to create exclusive designs. Fixture manufacturers watch closely all possible sources of inform ation as to the remodelling of old buildings CT the construction of new ones, and as soon as the slightest clew to the ownership can be obtained
 merry war of competition IS started, At the first sign of encouragement, or of ten before, the lighting engineer pre- sents his card to the architect with q request to look over the plans for data upon which to base his estimate.
 There Is scarcely a hall. club, church or other public building in the city where special designs do not play an important part, and .he degree to which they are exclusive determines the cost As a matter of fact they are the cream of the manufacturers business, and most of them come high in more than one sense of the term,
 In actual practice the lighting expert is both engineer and artist; for his work, whether it be the designing of an electric sign, the lighting of store window or the illumination of pal ace, is to achieve artistic effects as we'll as the more practical results of proper distribution and minimum cost of maintenance by the application of scientific principles of light intensity and diffusion. Opticians insist that the majority of weak and strained eyes are due to improper arrangement of lights and disregard of the prim- ary optical law that no light should enter the eye direct from the luminous center. To this law modern practice has added certain other requirements, which say that practical illumination must include usefulness, economy In distribution and control and that har- mony of design and arrangement upon which the architect has learned to re- ly for the full expression of hls own iedas and the spirit of the building, as absolutely as the painter relies of | the building, as absolutely as the painter relies upon the soft neutral tints, high lights and delicate half
 tones for the protection of his picture.
 In every such building the illumina- tien and accessories are made to cor
 respond with the architectural lines and decorations Thus in @ theater the quality of the light must be soft and
 well distributed, as a restful contrast to the glare of the footlights, In the | lighting of churches a great diversity of architecture has to be considered, | from the ornate Greeian or Corlnthlan,
 where studded lights would be out of place, to the plalner Gothic and mod ern types, where this method of light | ing Is frequently seen, and the sym boiic bodies of the Episcopal and Rom an Catholic churches, which must be | illuminated in harmony with the cen tral idea of making the chancel beau-
 tiful and aesthetic. | Then there Is the other extreme, where the Puritanical ideas of plain ness and severity frequently find ex- pression in studded lights arranged in the form of cross, a star or circle
 to denote some religious theme,
 Tn the work of the lighting engineer one of the most important features to
 be considered is the color scheme; for 1 this will make wide difference in the 1 illumination of two rooms of different eolors with the same source of light. 1 For instance, 1t has been determined ] that a white wall will reflect S5 per l cent. of the light which falls upon it; . -a-L |