The scientific discussions of forms of bulbs, the material of reflectors and the forms of shades, are very interesting. So is a series of “demonstration room tests,” especially No. 11,[209] showing a fine diffused light, thrown from a concealed bulb by a reflector at the ceiling.
“Even more important than the economic side of the subject is the disastrous effect on the eyes caused by numerous common artificial lighting arrangements.”
“The ruin of eyesight now common with artificial light is due to the fact that so few people understand the importance of the proper placing, reflecting, and shading of artificial lights.”
“In order not to injure or fatigue the eye, the following points should be avoided:—
- Flickering light,
- Glaring lights,
- Glare reflected from paper,
- Light from unusual angles,
- Too little light,
- Too much light,
- Streaks of light,
- Sharp contrasts of dark and light.”
“In the lighting of desks there are five principal requirements:—
- The lamp should be out of the line of vision.
- Have no regular reflection or glare from paper.
- Have the light free from streaks.
- Avoid too great intensity.
- The light should be steady.”
- [I add: Don’t get in your own shadow.]
“The three reflectors best suited to lighting the shelves of the library are the opal dome, the fluted opal cone, and the prismatic reflectors.”
Indirect lighting. This is defined thus: “The lamps themselves are not visible. They are placed in cup or vase or trough mirror-reflectors, from which the light is thrown up towards the ceiling, to be thence reflected down into the room.”