Ever since men abandoned their nomadic life and started growing their own food, they have been trying to influence the weather. That simply meant pleasing the weather gods by offering prayers, dances and sacrifices, a practice that went on for thousands of years and still continue to this day. It was not until the close of the 19th century that more drastic measures were taken towards weather modification. One of the first devices tested was the “Hail Cannon”.

The Hail Cannon is a funnel-shaped device that supposedly disrupt formation of hailstones by creating shock waves. An explosive mixture of acetylene and oxygen is ignited in the lower chamber of the machine. As the resulting blast passes through the neck and into the cone, it develops into a shock wave, which then travels at the speed of sound through the cloud formations above. It’s believed that the shockwave disrupts the growth phase of hailstones.

A modern hail cannon at a field in Germany. Photo credit