Hand grenades were used off and on since the invention of black powder, appearing in small numbers in such conflicts as the American Civil War. However, they did not really come into common use until the trench warfare of World War I made them invaluable.

Interestingly, the glass Civil War model led to an intruiging peacetime use - the glass bottle fire extinguisher grenade. Made from the mid 1800s to the early 1900s, these glass bottles were filled with water and fire retardant chemicals. They were to be thrown into the fire and shattered. The water and chemicals would mix and produce a retardant gas.

In World War I, enterprising troops began to make primitive grenades with jars filled with gunpowder, rocks and a simple, often unreliable, fuse. The ideal fuse burned about three to five seconds -- enough time to throw the grenade into the opposing trenchlines, but not enough time for it to be caught and returned.

As the utility became obvious, standard grenades started to appear. The german "stick" grenade was tossed more like a knife, as opposed to the baseball-like American models.

The tendency of a grenade to explode messily, killing anyone nearby leads to the expression "Close only counts in horseshoes and hand grenades" - although in the modern era we have many other weapons of mass destruction that qualify for similar reasons.

For those of you with destructive endeavors, this might be for you. But keep in mind, making this is probably illegal, and not very nice.

Don't blame me if you see many one-eared bunnies, flopping around helplessly.

This specific model was used quite a bit in WW2, mostly by desperate snipers.

You will need:

• A tin(steel) can.
• A chisel, or large knife, or even a pointy rock.
• A stick of dynamite.
• Rocks or broken glass, or anything that hurts, when propelled at high speeds.
• A match or lighter (presumably)

1. Open the tin can by making a 'X' at the top and then pulling the corners away from the middle.

2. Discard of any contents that may have been in the can. If your can had any botulism in it, good for you, just another way to hurt your opponent.

3. Hold the stick of dynamite in the center, with the stick not touching the bottom.

4. While holding the dynamite, fill the rocks or broken glass in around the stick.

5. Once the can have been sufficiently, but not overly filled with the propellents, fold the corners of the cut tin can back in place. Do this while taking care to secure the dynamite stick in place with the sharp corners of the can.

6. Light the dynamite.

7. Throw the can, with propellants and dynamite. Throw it far away.

8. Run away.

You have just made and used a very destructive hand grenade.

"O Lord, bless this Thy hand grenade that, with it, Thou mayest blow Thine enemies to tiny bits in Thy mercy. And the Lord did grin, and the people did feast upon lambs and sloths and carp and anchovies and orangutans and breakfast cereals and fruit bats and large chu..."*

The hand grenade was first used in combat in the 15th century, but proved unreliable. Napoleon later experimented with 'grenadiers', infantry soldiers chosen for their strength and throwing abilities, but it was not until the First World War that the grenade really found a niche it was comfortable in.

Trench warfare was the ideal environment for hand grenades, essential for cleaning out those 'hard to reach' trenches and fox holes. At the beginning of the war the Allied forces had virtually no grenades available, rather unfairly the Germans were well equipped, with concussion stick, contact exploding disc and round fragmentation grenades. This inequality led to the manufacture by allied soldiers of glass jars filled with explosives, metal and a hand lit fuse. Later in the war the Mills bomb was developed, an effective fragmentation grenade, and grenade warfare dominated trench warfare thereafter. Teams were formed of two throwers, two carriers, two gun/bayonets for defense, two spare men for replacements and an officer if you were lucky. Once an enemy trench was reached, the throwers ran down the trench tossing grenades into each hole. During the war it is estimated that 70 million Mills bombs were produced.

Types of fuse

In the early days of grenade development there were two methods of detonation, timed fuse or contact. The contact method, where a trigger was armed and actuated by a shock or jolt, proved highly unpopular with troops due to the frequency of accidental "Ooops, Bob, are you O.K. Bob? Bob?" detonation. This type was phased out, and now Bobs around the world use...

Timed fuses are normally chemical reactions, timed to between 3-7 seconds and activated by pulling a pin. The pin itself is holding a spring loaded lever (The handle/bar on the side of the grenade) and the fuse does not activate until this lever is released, typically upon throwing the grenade. Thus it is theoretically possible to replace the pin, if the lever has not been released, but remember, once you have pulled the pin, Mr. Grenade is no longer your friend. The spring lever is surprisingly strong on a grenade, the pin almost certainly bent upon removal and with stress induced sweating of the hands and adrenaline shake, repining a grenade may not be the smart option. Throwing it would be the popular choice, with distance required dependant on the type of the grenade.

Types of grenade

Fragmentation grenades - such as the Mills bomb and American M67 are designed to have the casing disintegrate into up to 2000 tiny pieces of love. Effective killing radius of 5 meters, casualty radius 15 meters and fragments as far as 230 meters. The average person can throw a grenade 40 meters (not as far for children) so you may want to run or duck after tossing one of these, noting that if running, run the opposite direction to the throw.

Concussion grenades, such as Stielhandgranate 24 (German 'potato masher') rely on the explosion itself rather than the debris to inflict damage. Thus unless you are in a confined space, you won't have to retreat so far. If inside however, the next room might be the place to head for.

White phosphorous grenades, such as the M34 are often known as 'Willie Petes'. Despite this friendly name, if you find yourself holding one of these, a really enthusiastic throw is called for. White phosphorous ignites in air, burns through body armor and has the habit of fragments cauterizing themselves into your flesh. This puts the fire out, but when later these fragments are removed, they will re-ignite, often getting blown back out of the flesh by steam, at whoever was helpful enough to be removing them. White phosphorous also has a tendency of chemically reacting with tissue to prevent normal healing, should you be lucky enough to survive.

Incendiary grenades are designed to destroy equipment and start fires, so no problems here unless you are standing in a pool of gasoline. A simple lob into your neighbour's garden should be sufficient.

Stun grenades are typically used in hostage situations or on peaceful demonstrations, because of the limited permanent damage they cause. Using a pyrotechnic metal oxidant mix of Magnesium and ammonium, they confuse, disorientate and momentarily distract, much like recreational drugs but with a loud bang. Cover your ears, close your eyes and you should be O.K.

Smoke grenades are used for signals and cover thus cause little damage, so if your children have been begging you for a grenade for their birthday, this type is perhaps the responsible choice for parents.

Mustard gas grenades often are marked with a reassuring skull and crossbones, or other poison linked theme. Wind direction and swift relocation should be factors to consider here, holding your breath should not be considered an option.

Tear gas grenades, now is the time to hold your breath, deliberate breathing should be limited to the extremely macho 'I want cry and throw up' individual or contestants on the Fear Factor T.V. show.

Molotov Cocktails are tricky and care should be taken when throwing. A simple overarm pitch may dump flaming liquid down your arm and back so try instead for the ungainly straight arm sideways lob, commonly seen in riot footage.

Photon grenade, if you find yourself holding one of these, then you are a delusional Star Trek fan, so set it to the lowest of its 20 settings and then get a life. Join some non-trek related clubs, make an effort to meet new people and get out of the house more.

* Monty Python and the Holy Grail.