Petard

From Wikipedia, the free encyclopedia

This article does not cite any references or sources. (September 2007)
Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed.

The petard by Francis Grose, 1812

A 19th-century British army petard

A petard was a medieval small bomb used to blow up gates and walls when breaching fortifications. In a typical implementation, it was commonly either a conical or rectangular metal object containing 5 or 6 pounds of gun powder, activated with a slow match used as a fuse. It was often placed either inside tunnels under walls, or directly upon gates. When placed inside a tunnel under a wall and exploded, large amounts of air would often be released from the tunnel, as the tunnel collapsed. By securing the device firmly to the gate, the shape of the device allows the concussive pressure of the blast to be applied entirely towards the destruction of the gate. Depending on design, a petard could be secured by proping it against the gate using beams as shown on the left, or nailing it in place by way of a wooden board fixed to the end of the petard in advance.^[1]

A petard mortar was the demolition weapon fitted to the Churchill AVRE tank. It was a mortar of a 290 mm bore, known to its crews as the "flying dustbin" due to the characteristics of its projectile: an unaerodynamic 20 kg charge, sufficient to demolish many bunkers and earthworks and even disable a Tiger tank, which could be fired up to 100 m.

In Maltese English, home-made fireworks—a popular and widespread albeit highly dangerous hobby in Malta—are called petards (the word in Maltese, murtal, is obviously related to "mortar"). In Malta, petards are detonated by the dozen during feasts dedicated to local patron saints. Maltese petards are made by common people without formal education in chemistry, as an exercise in traditional handiwork. Consequently, safety is frequently neglected and fatal accidents are common.

Etymology: Middle French, from peter, to break wind, from pet expulsion of intestinal gas, from Latin peditum, from neuter of peditus, past participle of pedere, to break wind; akin to Greek bdein to break wind. (Merriam-Webster) Petard remains a French word meaning a firecracker today.

[edit] "Hoist by his own petard"

The word remains in modern usage in the phrase to be hoist by one's own petard, which means "to be harmed by one's own plan to harm someone else" or "to fall in one's own trap", literally implying that one could be lifted up (hoisted, or blown upward) by one's own bomb. Shakespeare coined the now proverbial phrase in Hamlet.

In the following passage, the "letters" refer to instructions (written by his uncle Claudius, the King) to be carried sealed to the King of England, by Hamlet, Rosencrantz and Guildenstern, the latter being two schoolfellows of Hamlet. The letters, as Hamlet suspects, contain a death warrant against Hamlet, who will later open and modify them to instead request the execution of Rosencrantz and Guildenstern. Enginer refers to a military engineer.

There's letters seal'd: and my two schoolfellows,

Whom I will trust as I will adders fang'd,

They bear the mandate; they must sweep my way

And marshal me to knavery. Let it work;

For 'tis the sport to have the enginer

Hoist with his own petar; and 't shall go hard

But I will delve one yard below their mines

And blow them at the moon: O, 'tis most sweet,

When in one line two crafts directly meet.

After modifying the letters Hamlet escapes the ship and returns to Denmark.

In medieval and Renaissance siege warfare, a common tactic was to dig a shallow trench close to the enemy gate, and then erect a small hoisting engine that would lift the lit petard out of the trench, swing it up, out, and over to the gate, where it would detonate and hopefully breach the gate. It was not impossible, however, that this procedure would go awry, and the engineer lighting the bomb could be snagged in the ropes and lifted out with the petard and consequently blown up. Alternately, and perhaps a more likely scenario, if the petard were to detonate prematurely due to a faulty or short slow match, the engineer would be lifted or 'hoist' by the explosion.

Thus to be 'hoist with his own petar' is to be caught up and destroyed by his own plot. Hamlet's actual meaning is "cause the bomb maker to be blown up with his own bomb", metaphorically turning the tables on Claudius, whose messengers are killed instead of Hamlet. Also note here, Shakespeare's probable off-color pun "hoisted with his own petar" (i.e., fart) as reason for the spelling "petar" rather than "petard".