G.B. Halsted

G.B. Halsted was a mathematics teacher at the University of Texas at Austin in the early twentieth century. He was interested in and a supporter of non-Euclidean geometry and translated its two founders, Janos Bolyai's and Nikolai Lobachevsky's, books about it into English. He advocated teaching non-Euclidean geometry in high school instead of traditional Euclidean geometry, which he viewed as obsolete.

Source A History of Mathematics Education in the United States and Canada National Council of Teachers of Mathematics (NCTM) yearbook.