20 MR. JOHN GRAHAM ON CONSUMPTION 
previously and have since ascertained that the Dukinfield 
and Worsley coals gave the same result. 
Command was always had of the draught. The tempera- 
ture in the flue at the bottom of the chimney, during some 
periods of the day, was sufficient to melt lead but never 
zinc. 
V. Series oF EXPERIMENTS. 
Fig. 7. 
| 
I 
| 
[| 
Li 11 
GRY. BAe cy eer A , wie 15 Feet 
Y 
The boiler first experimented with was of the shape 
shown in the annexed drawing, and commonly called in 
this neighbourhood the “breeches boiler.’ It has two 
interior fire-places which join behind the bridges and form 
one direct flue through the interior of the boiler. It was 
23 feet 3 inches long, 8 feet in diameter. 
