d regulate the supply of coals dropping down into the
fireplace, regulate the speed of the travelling furnace by means of the
ratchet, clean out the ash-hole of clinkers every two hours and wheel
them out of the stoke-hold, regulate the water-supply to the boilers,
and keep the steam at the proper pressure, and rectify any and every
derangement and mishap that occurs to the self acting stoker.

30. _Question._--But are not these "self-acting stokers" smoke consumers
as well?

_Answer._--The self-acting stokers have to be kept working by the live
stoker, and are smoke consumers so long as the coals let down on the
travelling furnace is exactly proportionate to the requirements of it,
but if the supply should exceed what is necessary, the grate becomes
choked with coals and has to be cleared of some of them, and in doing
this with coals partly burnt, smoke is inevitable; and if the supply is
insufficient, the grate becomes bare of fuel, and cold air finds its way
through the bars and checks the steam. To remedy this, the coal is let
down and carried onward by the moving grate before they can be ignited,
and soon begin to smoke, so that in these two extremes, too much or too
little coals will cause smoke; but if this type of furnace is in charge
of a competent stoker, there is little chance of the bars being choked
with coals, or starved for want of them.

31. _Question._--Is it not possible to consume the smoke of a boiler
furnace independent of patents and mechanical contrivances that can
only be worked by an experienced stoker?

_Answer._--I have proved it possible where several boilers were
connected and working, and using small and smoky coals. In an
establishment in West London the system in vogue was in this manner: all
the bridges were built hollow, and an iron flap covered the bottom of
the bridge, and a long iron rod from the flap was carried to the front
of the boiler, and an inch steam pipe with cock attached entered the
fireplace above the door, and was joined to a two-inch perforated pipe
that was fixed from left to right over and above the dead-plate. When
the fires required replenishing, the flap was opened, then the door and
steam cock, and six shovelfuls of coals were hastily thrown in evenly
over the fire, and the door was then shut. The result of this
performance was a mixture of steam and smoke observable at the chimney
top, the steam was kept on while any smoke was visible; then the next
boile