"Industrial Espionage is the Driving Force Behind Technical Progress in Radio Tube Technology"

"A study of vacuum tube technologies developed in France during World War I is conducted. The role of military intelligence and industrial espionage in the development of the French TM triode is noted. The designs of vacuum tube triodes by Henry Abraham, Michel P\u00e9ri and Jacques Biguet, Beauvais and the Junot detector triode are studied. The invention of the multivibrator by Abraham and Bloch is considered in detail. Abraham and Bloch's priority in the invention of the vacuum tube self-oscillating multivibrator circuit is shown."