DUTY OF INCANDESCENT ACETYLENE BURNERS.--Granting that the petty troubles
and expenses incidental to incandescent lighting are not considered
prohibitive--and in careful hands they are not really serious--
and that mantles suitable for acetylene are employed, the gas may be
rendered considerably cheaper to use per unit of light evolved by
consuming it in incandescent burners. In Chapter VIII. it was shown that
the modern self-luminous, l/2-foot acetylene burner emits a light of
about 1.27 standard English candles per litre-hour. A large number of
incandescent burners, of German and French construction, consuming from
7.0 to 22.2 litres per hour at pressures ranging between 60 and 120
millimetres have been examined by Caro, who has found them to give lights
of from 10.8 to 104.5 Hefner units, and efficiencies of from 2.40 to 5.50
units per litre-hour. Averaging his results, it may be said that
incandescent burners consuming from 10 to 20 litres per hour at pressures
of 80 or 100 millimetres yield a light of 4.0 Hefner units per litre-
hour. Expressed in English terms, incandescent acetylene burners
consuming 0.5 cubic foot per hour at a pressure of 3 or 4 inches give the
duties shown in the following table, which may advantageously be compared
with that printed in Chapter VIII.
Pages:
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552