276 
Statistics* 
With a view that the plan of this boiler should be submitted to 
the citizens of the United States who wish to embark in steam 
engine machinery, I hand it to you to decide whether it is worth a 
place in your work now publishing or not. 
With great respect, 
FREDERICK GRAFF, 
Su/ierintendant of the Philadelphia water works. 
Thomas Cooper, Esq. 
The plan is drawn to a quarter of an inch to the foot. 
The perpendicular heater A* may be raised in size and situa- 
tion to suit the idea of the builder. 
The dotted lines in plan B, represents the flues C, above the 
fire bed, and which pass out of the boiler into the stack, at the 
mouth of which the damper is fixed. 
D, the fire grates. 
E, the door way, which can be so arranged, if required, to con- 
sume the smoke by lowering the fire bars or grates. 
F, the water line six inches above the flue. 
G, a section through the fire place, showing the front range of 
perpendicular heaters and the horizontal flues above, with coal 
grate and ash pit. 
STATISTICS. By the editor. 
Eight grain gallons of 268,8 cubic inches to the gallon make 
Orte Winchester bushel of grain ; struck, that is even with the sur- 
face; The bushel ought to contain 2150,42 cubic inches : it ought 
to be 18,5 inches diameter throughout and eight inches deep. In 
England it is well settled as an indictable offence to buy or sell by 
any other bushel : I strongly incline to think, that it is indictable 
to buy or sell by any other bushel, here also : for I know of no 
other legal bushel. 
Retailers in this country, generally sell every commodity what- 
ever by the wine gallon of 23 1 cubic inches, without regard to the 
measure by which they purchase. Malt liquor is sold in England 
by the ale gallon of 282 cubic inches, being to the wine gallon, as 
c:ie pound avoirdupois is to one pound troy. It is high time we 
