**Adolf Kiefer**'s father Jakob was a farmer, as well as the village's mayor and a member of the cantonal parliament. Adolf first attended primary school in Selzach, then the Bezirksschule in Grenchen, and finally the Kantonsschule in Solothurn. In 1876 he matriculated at the Polytechnic in order to study mathematics and physics in the Department for Mathematics and Physics Teachers. Four years later he obtained his diploma as mathematics teacher.

His first teaching post was at the Concordia Institute, a college in Zürich, from 1881-1882. He also seems to have attended lectures at the University of Zürich, though the university's matriculation register only lists his son Adolf (1892-1951) [3]. In any case Kiefer senior obtained his doctorate from the University of Zürich in 1881 for his thesis *Der Kontakt höherer Ordnung bei algebraischen Flächen* Ⓣ. From 1882-1894 Kiefer taught geometry and technical drawing at the Kantonsschule in Frauenfeld (canton Thurgau), primarily at the school's vocational section, the Industrieschule. In 1886 he became deputy head and two years later headmaster. However, 'much to the regret of his superiors, colleagues and pupils' [2] he left the school in 1894, as he became Director of the Concordia Institute. The college was closed after the First World War, but Kiefer found teaching posts at the Kantonsschule, the technical college and the teachers' college in Zürich.

Kiefer published almost forty papers, most of which are on geometry. Among his papers are *Über Kräftezerlegung* Ⓣ (1904), *Über die Kettenlinie* Ⓣ (1915), *Von der Cykloide* Ⓣ (1917), *Zum Normalenproblem bei den Flächen zweiten Grades* Ⓣ (1921), and *Zwei spezielle Tetraeder* Ⓣ (1925). He became an honorary member of the Schweizerische Naturforschende Gesellschaft in 1928.

Kiefer joined the enlarged committee of the first International Congress of Mathematicians, as well as the committee in charge of board and lodging, in December 1896. His duties included organising accommodation for the Swiss secondary school teachers who attended the congress -- a certain Mr Bertsch, of the Concordia Institute in Zürich, offered Swiss teachers free accommodation there in July 1897.

Adolf Kiefer retired in 1926 after having fainted in his classroom. He died three years later.

**Article by:** Stefanie Eminger, University of St Andrews