# lituus

The lituus is a spiral curve that was discovered by the
English mathematician Roger Cotes (1682–1716) and named by the Scottish
mathematician Colin Maclaurin in 1722.
The Latin *lituus* refers to a staff shaped like a bishop's crosier.
The lituus is the locus of a point that moves
in such a manner that the area of a circular sector remains constant. The
equation of the curve in polar coordinates is

*r*

^{2}=

*a*

^{2/π}