The missile of compressed air is created when a small quantity of acetylene gas metered into a chamber in the cannon’s breach is ignited by a spark supplied from a battery or other electrical source.

The result is an ear-splitting blast and an overwhelming rush of compressed air through the cannon’s mouth. Each blast travels hundreds of feet, hopefully far enough to reach the threatening clouds.

Uninitiated observers might suspect that war has broken out. With lightning often a feature of hail storms, the accompanying thunder coupled with the cannon’s blasts results in an impressive aerial acoustic display. It might be the Fourth of July, except that it’s February.

Most of the cannons used in fruit orchards and those shown in historical records feature barrels 10-20 feet long, as much as two feet across at the mouth, tapered from a smaller diameter at their breach.

Historical records say the blasts from cannons aimed horizontally easily knocked down advancing columns of the enemy, and their deafening roar caused advancing troops to cower and scatter.

Those earlier military uses had to forego the convenience of acetylene gas delivered by the local supplier, but explosive materials and ways to ignite them have been part of military operations for centuries. They were no less impressive - or effective - than today’s applications.