chain turns down over the roller at the extremity of the furnace. In
Messrs. Maudslays' plan of a self-feeding furnace the fire bars are formed
of round tubes, and are placed transversely across the furnace. The ends of
the bars gear into endless screws running the whole length of the furnace,
whereby motion is given to the bars, and the coal is thus carried gradually
forward. It is very doubtful whether any of these contrivances satisfy all
the conditions required in a plan for feeding furnaces of the ordinary form
by self-acting means, but the problem of providing a suitable contrivance,
does not seem difficult of accomplishment, and will no doubt be effected
under adequate temptation.

164. _Q._--Have not many plans been already contrived which consume the
smoke of furnaces very effectually?

_A._--Yes, many plans; and besides those already mentioned there are
Hall's, Coupland's, Godson's, Robinson's, Stevens's, Hazeldine's, Indie's,
Bristow and Attwood's, and a great number of others. One plan, which
promises well, consists in making the flame descend through the fire bars,
and the fire bars are formed of tubes set on an incline and filled with
water, which water will circulate with a rapidity proportionate to the
intensity of the heat. After all, however, the best remedy for smoke
appears to consist in removing from it those portions which form the smoke
before the coal is brought into use. Many valuable products may be got from
the coal by subjecting it to this treatment; and the residuum will be more
valuable than before for the production of steam.



STEAM.