Hendrik van der Bijl

Pieter van der Bijl had been an ox-wagon driver between Cape Town and Kimberley and moved to Pretoria in 1887 where he became a prosperous grain and produce merchant.

[1][2] After the ill-fated Jameson Raid (1895) there was increased tension in the Transvaal Republic, of which Pretoria was the capital, and the young Van der Bijl assisted his father in stacking rifles and ammunition collected by the Boer forces in preparation for further British attacks.

[3][5] He obtained his PhD in March 1912 and was appointed assistant in physics at the Königlich Sächsische Technische Hochschule in Dresden, where he worked under Wilhelm Hallwachs.

[4] He is now perhaps best remembered for the van der Bijl equation which describes the relationship of the three 'constants' of a vacuum tube, the transconductance gm, the gain μ and the plate resistance rp or ra.

[2][3] Van der Bijl realised the advantages of a state-controlled company with capital provided by the state but run on commercial lines as a public concern.

[3] It was a commercial success, South Africa was assured of sufficient inexpensive power for its fast-growing industries and ESCOM was able to pay back the state loan after 10 years.

South Africa was an important supplier of spares, guns, ammunition, bombs, armoured cars, clothing, boots, blankets and canned foods to the Allies.

[3][4][8] He had a hand in establishing more than a dozen South African institutions including: In 1915 Van der Bijl married Florence Wagner, an American who he met as a music student in Germany.