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

a + a, signifies a added to a, or 2 a.

a – a, denotes a less a, or 0.

a × a, a multiplied by a, or a square, a² (see below).

a ÷ a,}
}	a divided by a, or 1.
or a a}

a², the square of a, or a × a

a³, the third power of a, or a × a × a.

√a, the square root of a, or a^½

∛a, the cube or third root of a, or a^⅓

a + b + c
d, shows that the sum of a, b, and c, is to be divided by d.

(a + b + c) d or a + b + c × d, denotes that the sum of a, b, and c, is to be multiplied by d.