1891 saw him also appointed to the professorship of Geometry at Gresham College; here he met Walter Frank Raphael Weldon, a zoologist who had some interesting problems requiring quantitative solutions.
En 1891, converteuse en profesor de Xeometría no Gresham College, onde coñeceu a Walter Frank Raphael Weldon, un zoólogo que tiña uns interesantes problemas que requirían solucións.