"S"
Scales 

S 
The S scale is a scale of sines and cosines,
running from 5.7° to 90°. Select the degrees on this
scale and read the sine or cosine on the C/D. The
magnitude on the C/D scale will be from 0.1 to 1.0. Formula: S = sin X 
Sh_{1} Sh_{2} 
The Sh_{1} and Sh_{2} scales
are used in electrical engineering calculations, and
calculate the hyperbolic sine function. Sh_{1}
ranges from 0.1 to 0.89, while Sh_{2} ranges from
0.89 to 3.0. These scales are available for use on the
top or bottom rules. Formula: Sh_{n} = sinh X 
SRT 
The SRT scale (formerly ST scale) extends the
S scale for smaller angles between 0.56° and 5.8°. The
values on this scale range from 0.01 to 0.1 read from the D
scale. In this range, sines and tangents are nearly
equal so this scale can be used for both. Formula: SRT = sin, tan X 
S_{mann} 
The S_{mann} scale in iSlideRule is
another representation of the SRT scale, for small
angles. This scale ranges from 0.57° to 5.7°. Formula: S_{mann} = sin, tan X 