OCR Text |
Show DIFFERENT AMOUNTS OF LIGHT NEEDED A survey shows that 22 per cent of children finishing grade school have damaged eye sight. When they have finished college, 40 per cent are so affected. At age forty, 65 per cent suffer from visual defects. And at age sixty, 95 per cent have eye defects. de-fects. This regrettable increase In eye troubles Is In many Instances caused by eye strain resulting from reading, read-ing, studying, sewing at night with poor light and not enough light. Science measures light In terms of foot-candles. A foot-candle Is the amount of light one standard candle can-dle shines on t surface one foot away. For seeing one's way around and performing ordinary tasks which do not require seeing very small objects, ob-jects, 5 foot-candles is sufficient. For reading coarse print and large stitch sewing, you can get along with 10 foot-candles. For continued reading of ordinary print, or doing ordinary sewing, you need at least 20 foot-candles. For reading fine print and fine sewing, you require 30 foot-candles, or more. Your light may look bright, but It Is the Illumination you get on your work that saves your eyes from strain; and this diminishes rapidly the farther away you are from your lamp. Seated with your paper or work 3 feet away from your lamp, it will require re-quire a light of at least 275 candle-power candle-power to produce the 30 foot-candles needed to be certain your eyes have enough light to do their work without with-out danger of strain and permanent Injury. If you use electricity, your light company will recommend the right' size bulbs to use. If your home Is not wired, one of the new 300 candlepower kerosene or gasoline pressure mantle lamps will supply plenty of "live" natural light for every home need. It takes the pressure to give you all the light you should have. |