A STVDY THEORETICAL SCIENTIFIC & PRACTICAL CONSVLTING LIGHTING SPECIALIST VIII.--The Lighting of the Home NOTE.- Residence lighting is a matter with which, as a rule, the resident has little or nothing to say, the lighting arrangements being definitely made prior to his occupancy of the premises. In a discussion of appropriate lighting for the home, it is not glittering generalities which are desired. of sufficient breadth to cover the extreme as issue, the author presents the results of his and sketches. Samples of the glassmakers' continued in the next article.-Editor. HE problem of home. lighting resolves itself into a discussion of those conditions which can best be satisfied by the application of a few basic principles. It is indeed a wide gap between the city house and the threeroom flat-and the interval separating the city house and country house is equally hard to span. The tendency has been to limit lighting discussions to a consideration of isolated cases which are not representative because they are extremes, excepting the writings of manufacturers' press agents, which unfailingly prescribe one remedy for all lighting ills. The mind of the reader has been confused in attempting to differentiate between various forms of lighting equipment, whereas the real issue involves a co-relation of fundamentally important factors, without which the equation of light cannot be solved. It is, of course, necessary to consider extremes where thousands of dollars are expended upon the lighting of a single room, but it is more important to consider the other extreme where the entire lighting equipment of the small flat inust be restricted within the sum of one hundred dollars, including wiring, gas piping and fixtures. The subject requires practical suggestions, well as the average condition. In this work, accompanied by night photographs art are also shown. The subject will be In Germany the tenant is expected to bring his lighting fixtures with him, only the outlets being provided, which at least gives him the opportunity of satisfying individual requirements, and not being obliged to put up with lighting fixtures which do not illuminate in the implied sense. In discussing this subject, my object is to present a critique of residence lighting which includes an analysis of fundamental principles. which are violated in either the extremes or average condition, and first amongst these is the question of color of light involving a consideration of physiological and psychological phenomena. "Technically, the human eye must not be exposed to light sources having an apparent brightness greater than 5 candle power per square inch. The following table shows how we have exceeded the danger mark in the past few years: the increase in source brilliancy of our illuminants has been gradual, and the color of their light yellow up to the advent of the tungsten lamp, when an abrupt increase in apparent brightness and an equally abrupt change in color (from yellow to white) took place. "This change affected the lighting of the home in that the advertised economy of the new electric lamp (at that time discounted by its fragility) persuaded its adoption, under the impression that the white quality of light was desirable, being so advertised."* Considering first the effect of white vs. yellow light on the eye, we find that for centuries humanity has been accustomed to a white reading page (Fig. 1), made yellow by the color of artificial light, and that with each successive illuminant improvement the relative increase in brightness was offset by the color permanence of the light, which remained yellow. With the advent of the Welsbach mantle in 1887, following the first electric lamp in 1880, the eye was subjected to a change of color from the yellow gas flame to the (then) greenish-white incandescent gas mantle. The Welsbach makers, however, soon real Abstract from paper by F. Laurent Godinez on the Physiological and Psychological Functions of Artificial Light, read before the Hudson County Medical Society of the State of New Jersey. ized that a white light while suitable for color matching and other industrial occupations, where true color values are important, was unsuitable for lighting of the home, and therefore perfected a gas mantle which appears to the eye as agreeable and mellow as the oil lamp. With the advent of the tungsten lamp, however, no word of warning as to its dangerous intrinsic brilliancy or the unsuitability of its white light was forthcoming, and as a result, its adoption over the carbon filament type, for economic reasons, transformed the reading page from yellow to white (Fig. 2), thereby making reading more difficult, owing to the abrupt contrast of the small black type against the glaring white page (Fig. 2). While glazed paper causes sharp reflections of light, which blurs and obscures one's sight, an unglazed paper diffuses light without glare. It is too much to ask or expect of publishers that they immediately change their methods to compensate for the negligence of the illuminant manufacturer, who should print some few words of warning upon the boxes in which his lamps are sold, thereby having a far-reaching effect. It is equally unfortunate that there is no society organized for the purpose of discriminating between lighting equipment which is conducive to eye comfort, or absolutely unphysiologic. Regarding this question of white or yellow light, Mr. Wm. J. Beardsley, an architect, who is responsible for the New York State Penitentiary buildings, informed the writer that his draughtsmen (over fifty in all), who are employed from all sections of the country, are continually taking the tungsten lamps out of the sockets in the draughting room and substituting lamps of the carbon filament type, owing to their decided preference for a working light of a yellow amber tint, not causing too decided a contrast between the black ink and the tracing cloth or white paper. Thousands of letters have been received from those who have tried the experiment of reading with a white, or amber light, as suggested by the writer (through the medium of leading magazines and newspapers) and the expression of opinion is unanimous in favor FIG. 2. The idea of considering the effect of light, as it looks to the eye, is new and quite opposed to the "efficiencyeconomy utility' doctrine of most illuminating engineers, but when all has been said it is the eye alone which tells the story to the mind, and there is no reason why the "economy" of modern illuminants should not be utilized gracefully, in lighting which appeals to both the physiologic and aesthetic. The home is presumably a haven of rest. Repose is the one element which should predominate in its atmosphere. All reasoning is by comparison, whether by conscious or subconscious mental activity. The predominance of what may be termed the "white light effect" in office buildings, where thousands of workers engaged in clerical labor are obliged to ruin their eyesight by unnatural lighting which is unphysiologic to the degree superlative, has impressed the subconscious mind forcibly with an association of white light with working conditions. But the light in the home should not suggest to the tired mind of the business man the glaring lighting of the office, subway or shop window. A prominent opthalmologist The abrupt change from a yellow to a white reading page, with the advent of the tungsten filament lamp subjected the eye to a radical change from what it had been accustomed to by usage through centuries. of a yellow over a white as a reading light. It is a simple matter to satisfy one's self regarding this by substituting an amber light gas mantle for a white light gas mantle, or by placing over a tungsten lamp some translucent material, such as yellow silk, paper or gelatine film. One trial will convincingly demonstrate my contention, which applies equally to installations of indirect lighting, where the remedy lies in placing a film of yellow gelatine over the silver-plated reflectors, so that a white ceiling becomes a diffuser of yellow instead of white light, after which the ceiling can be permanently tinted the proper color. Up to this point I have discussed the physiological aspect with reference to the reading page alone, my object being to indicate one physiological requirement of good lighting, which applies with equal force to the opposite extremes represented by the plebeian's tenement or the patrician's mansion. There is another very good reason why a yellow light is more desirable for the home, and that has to do with the actual appearance of a room's occupant as influenced by the color of light therein. states: "So many of my patients suffer whenever they go out at night, that it has become necessary to prescribe auxiliary glasses opaque to ultra-violet light (amber in tint) to be worn over their refracting lenses, in order to subdue the excessive glare which the eye is exposed to from all sides in these days of unphysiologic lighting." The engineering element seems utterly at a loss to comprehend why a light ap The general lighting of an interior representing the typical apartment. Indirect lighting from a reflector concealed within the shade of the table lamp causes light to be reflected from the outer surface of the bowl hanging from the ceiling. proximating the harsh white day-light effect is not desirable for the home at night. In their endeavor to imitate Nature so closely, they have evidently forgotten that the setting sun indicates. a period of rest-in the Creator's planand that an attempt to turn night into day is diametrically opposed to Nature's teachings. But it is entirely natural to emphasize the peace and quiet of eventide in the home by lighting which is subdued yet harmonious-in itself a symbol of repose to the eye. It is amazing to note the transformation of an interior effected by changing from white to amber light-for the white light, which is so unkind to the features, creates likewise a garish atmosphere, showing everything to its worst advantage. The rich brown, yellow, gold and red tones, which predomi nate in furniture and decoration, are rendered flat and lose all their warmth and feeling. Architectural draftsmen should try this experiment of changing a white to an amber light and observe the pleasing modification. As to the design of lighting by the architect, providing for this subject of color, the question naturally arises as FIG. 4. Effect of local lighting in the same room, from the same lamp with three small lamps lighted within the lower portion of the outer silk shade. Variety in lighting, as in other things, is desirable. to the advisability of modifying the color of the source itself, or accomplishing the desired effect by enclosing the source within some color-modifying device. Maintenance is always an important subject to be considered, and very often through negligence a lighting arrangement, which was quite effective when first installed, becomes entirely unsatisfactory by substitution of wrong sized lamps. Assuming that amber light gas mantles, or tungsten lamps with ambertinted bulbs, were specified by the architect, what assurance could he have that these would not be replaced by white light lamps, as renewals? The better plan is for the architect to design equipment for residential use, |