Found in "l'année scientifique 1912" in an article about military use of aircraf, this curious description which reads like a 1945 German secret weapon but must be a 1912 French (even more secret) weapon. Unfortunately no name is given . Any idea ? (translated roughly by myself) "Against airplanes, a new weapon is born. That's un gun fixed on the ground and able to fire vertically. It is loaded with an explosive such as, without any need of a projectile , the explosion of the explosive generates an ascending atmospheric perturbation. Air is violently moved along the outer surface of a cone oriented with its point at its lower part. It has been observed that a ring of air was moved rapidly with a sufficient force to break at a range of 300m a steel cable. This result proves that an army with such guns could create a protected zone above it which no aircraft could enter up to 500m height"
