In choosing the source of our light, the great points to be considered
are, first, the influence on the eyes, and secondly, economy. It is
poor economy to use a bad light. Modern houses in cities, and even in
large villages, are furnished with gas; where gas is not used,
sperm-oil, kerosene or coal-oil, and candles are employed. Gas is the
cheapest, (or ought to be;) and if properly used, is as good as any.
Good sperm-oil burned in an Argand lamp--that is, a lamp with a
circular wick, like the astral lamp and others--is perhaps the best;
but it is expensive and attended with many inconveniences. Good kerosene
oil gives a light which leaves little to be desired. Candles are used
only on rare occasions, though many families prefer to manufacture
into candles the waste grease that accumulates in the household. The
economy of any source of light will depend so much upon local
circumstances that no absolute directions can be given.
The effect produced by light on the eyes depends upon the following
points: First, _Steadiness_. Nothing is more injurious to the
eyes than a flickering, unsteady flame. Hence, all flames used for
light-giving purposes ought to be surrounded with glass chimneys or
small shades.
Pages:
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541