In 1838 George Airy worked out the proof for the explanation given by Christian Huygens in 1678 that this curve was the catacaustic of a circle when the light source is infinity. The evolute of Cayley's sextic, this curve is essentially a two-cusped epicycloid formed by a ci
In 1838 George Airy worked out the proof for the explanation given by Christian Huygens in 1678 that this curve was the catacaustic of a circle when the light source is infinity. The evolute of Cayley's sextic, this curve is essentially a two-cusped epicycloid formed by a circle of radius A rolling externally on a fixed circle of radius 2A. FTP name this curve, given its modern name in 1878 by R.A. Proctor, who thought that its shape was reminiscent of a kidney.
In 1838 George Airy worked out the proof for the explanation given by Christian Huygens in 1678 that this curve was the catacaustic of a circle when the light source is infinity.
nephroid