COST PER HOUR AND HYGIENIC EFFECT OF LIGHTING BY DIFFERENT MEANS
The data (except in the column headed "cost per 100 candle-hours") refer
to the illumination afforded by medium-sized (0.5 to 0.7 cubic foot per
hour) acetylene burners yielding together a light of about 100 candle-
power, and to the approximately equivalent illumination as afforded by
other means of illumination, when the lighting-units or sources of light
are rationally distributed.
Interest and depreciation charges on the outlay on piping or wiring a
house, on brackets, fittings, lamps, candelabra, and storage
accommodation (for carbide and oil) have been taken as equivalent for all
modes of lighting, and omitted in computing the total cost. The cost of
labour for attendance on acetylene plant, oil lamps, and candles is an
uncertain and variable item--approximately equal for all these modes of
lighting, but saved in coal-gas and electric lighting from public supply
mains.
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| | | | | | |
| | |Candle- | Number |Aggregate| Cost |
| | |Power of| of | Candle- | per |
| | Description of | each |Lighting | Power | 100 |
|Illuminant.
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