distance, it will be readily understood that to light, for instance, the
floor of a moulding shop, a burner 6 feet from the floor will do as much
work as four burners, the same size, placed 12 feet from the floor. It is
therefore a most important matter that all lights should be as low as
possible, consistent with the necessities of the shop, as not only is the
expense enormously increased by lofty lights, but the air becomes more
vitiated and unpleasant, interfering with the men's power of working. Any
lights suspended, and, in fact, all workshop lights, must have a
ball-joint or universal swivel at the point where they branch from the
main, as they are liable to be knocked in all directions, and must,
therefore, be free to move to prevent accidents. It is better to have
wind-screens, if necessary, rather than glass lanterns, as not only does
the glass stop a considerable amount of light when clean, but it is in
practice constantly dirty in almost every workshop or yard.

[Illustration: PILLAR LIGHT OR PENDANT FOR WORKSHOPS.]

For bench work and machine tools, each man must have his own light under
his own control; and in this matter a little attention will make a
considerable saving. The burners should be union jets--_i. e._, burners
with two holes at an angle to each other--not slit or batswing, as the
latter are extremely liable to partial stoppage with dust. Where batswing
burners are used, I have often seen fully 90 per cent. more or less choked
and unsatisfactory; whereas a union jet does not give any trouble. It is
not generally known that any burner used at ordinary pressures of gas
gives a much better light when it is turned over with the flat of the
flame horizontal, until the flame becomes saucer-shaped, as I show you.
You can see for yourselves the increase in light; and in addition to this
the workman has the great advantage of a shadowless flame. In practice, a
burner consuming 5 cubic feet of gas per hour with a horizontal flame is a