The Lines of Striction on a Quadric

It is well known that the line of striction of a regulus on a quadric is a rational quartic of type (1,3) cutting every generator of the regulus at a single point and every generator of the other regulus in three points. The rational quartic curve R⁴ in [3] has been studied in detail from the projective point of view. In this paper, the metrical specialisations consequent to the metrical definition of the line of striction, and a few allied problems are considered.