Who was Harry Hart? It appears that some geometers who know about Hart's Theorem are not familiar with Hart's Inversors, and conversely.  Can someone locate a biographical sketch of Harry Hart?
As an aside, I must say that I was unfamiliar with Hart's Circle and his other contributions to geometry.  I found the following sites quite interesting: https://mathworld.wolfram.com/HartsTheorem.html,  https://mathworld.wolfram.com/HartCircle.html
https://en.wikipedia.org/wiki/Hart%27s_inversors
 A: I am one of the contributors to  X(50037), X(50038) and X(50040).
If you are looking for some information about the Hart who discovered Hart's theorem, not Harry Hart...
Hart's theorem and the Hart circle are due to Andrew Searle Hart (1811-1890). According to Wikipedia and MacTutor, he was an Anglo-Irish mathematician and vice-provost of Trinity College, Dublin.
From my understanding, Hart's theorem is, in a nut shell, Feuerbach's theorem for spherical triangles. You can view it as a generalization of Feuerbach's theorem where three sidelines are replaced by three circles, or Feuerbach's theorem in hyperbolic geometry. His original paper, "Extension of Terquem's theorem respecting the circle which bisects three sides of a triangle" (1861), is available on the Center for Retrospective Digitization in Göttingen (GDZ). See also John Casey's paper.
For his other papers, see here.
Seemingly he was also the author of "Geometrical investigation of Steiner's solution of Malfatti's problem," Quarterly Journal of Pure and Applied Mathematics vol. 1 (1856) 219–222.
A: There's a short biography of Harry Hart in Spanish at Wikipedia.
