Handbook of Railroad Construction; For the use of American engineers. / Containing the necessary rules, tables, and formulæ for the location, construction, equipment, and management of railroads, as built in the United States.

by George L. Vose

T = (2A)P × 2S
C,

Where T is the tractive power.

P, steam pressure in lbs. per square inch.

S, stroke in inches.

C, circumference of wheel in inches.

A, area of one piston in inches.

From this formula we get the values of the several factors as follows:—

The steam pressure, or P = TC (2A)2S.	(A.)
The stroke, or S = CT (2A)(2P).	(B.)
The piston area, or A = TC 4SP.	(C.)
The wheel circumference, or C = 2A × P × 2S T.	(D.)

And from (C) we get the diameter of piston by the following:—

d = √(area
.7854).