THE SMOKE ABATEMENT EXHIBITION* 
235 - 
In another series of grates the draught is taken downwards, 
or backwards, through the fire, so as to produce the same result,, 
the fire being first lighted in the usual way, and the draught 
taken up the chimney, and then, ’when the fire is well lighted, 
the upper draught is almost entirely stopped, and the gases are 
taken down through the fire, and the down-draught established. 
This plan has the objection that if the up-draught is not entirely 
stopped, a considerable portion of the smoke will pass up and be 
deposited as soot, w'hilst, if the up-draught is stopped, the fire 
is liable to smoke. 
Fetter’s '' Nautilus Grate ” is one of the best, both in appear- 
ance and design, in the Exhibition. The cross section resembles 
a shell, the fire being in the mouth. As the fuel becomes red- 
hot, it is pushed back, and fresh fuel is fed on in front. The 
upper part of the grate serves to regulate the amount of air 
admitted, and the products of combustion pass out by flues at 
the sides. By using this grate a very much greater proportion 
of the heat is utilised, for the products cf combustion, instead 
of passing directly into the chimney, pass out by side flues, and 
the top of the stove, as well as the front of the fire, radiate heat 
out into the room. The interior of the grate being lined with 
firebrick, the fire does not touch the metal. There is no smoke, 
for what is formed in the front is burnt in passing to the back 
of the fire. The combustion is so perfect that the fire remains 
granular, and ashes do not accumulate in the bottom of the 
basket. In summer the grate can be entirely removed, and its 
place taken by flowers, if wished, and there is no difiiculty in 
cleaning it. The expense with one of these grates is as little as 
Id. per day. 
In the second class of grates, in which hot air is supplied to 
the gases as they • leave the fire in order to complete their 
combustion, one of the most effective is Cornforth’s, in which 
the grate bars are hollow. The air, in passing through them. 
