OF COAL AND RATE OF EVAPORATION. 15 
Disturbing causes recognized during the performance of 
small boiler experiments in Table A. 
The First Experiment was rejected in consequence of 
the brickwork setting of the furnace being cold and damp. 
Second Experiment.— Barometer 29.4 inches ; hydro- 
meter dry bulb 69°, wet bulb 67°; weather clondy, with 
showers; draught strong; fired every 15 minutes; feed 
water 70°. 
Third Experiment. — Barometer 30 inches ; hydrometer 
72° dry, 70° wet; weather dry and clear; draught good; 
fired every 10 minutes; feed water 70°. 
Fourth Experiment. — Barometer 29.8 inches; hydro- 
meter 70° dry and 64° wet; heavy rain; draught good; 
fired every 40 minutes; the fire-place was nearly filled 
each time with coals; feed water 70°. 
Fifth Experiment. — Barometer 29.9 inches; hydro- 
meter 66° dry and 60° wet ; draught good; fired every 15 
minutes; the burning fuel was kept about 3 inches deep 
only. In consequence of the coals being of the usual 
irregular size, some parts of the bars became bare occa- 
sionally. eed water 70°. 
Sixth Experiment.— Draught strong; thickness of fire 4 
inches; feed water 60°. In other respects the same as 
fifth experiment. 
Seventh Experiment.— Draught slow; thickness of fire 3 
inches ; feed water 60°. In other respects the same as 
fifth experiment. 
Eighth Experiment.— Draught slower still; thickness of 
fire 3 inches; feed water 65°. In other respects the same 
as fifth experiment. 
Ninth Experiment.— A repetition of the sixth experi- 
ment. 
Tenth Experiment. — A repetition of the seventh experi- 
ment. 
