Given our recent discourses on arms and firearms I thought this might be an interesting fact about nothing at all....
Most of the world organizes their arms that fire projectiles, both large and small (artillery, firearms) around bore size. Of course the US usually does it with our usual 'odd' measurements of inches, while the rest of the world does it with meters. So there it is: a 90 mm mortar fires a.... 90 mm projectile. A .30 caliber rifle fires a 0.3 inch projectile. A 16" US battleship main gun fires a 16" projectile (shell). These are not precise measurements of the caliber's power but are 'close enough' for a rough idea.
But along come our British friends and put the 'whammy' on this whole thing and measure their artillery in.... wait for it.... pounds. Pounds? Weight? OK, so they refer to the artillery piece by its nominal weight. But wait (no pun intended), a '17 pounder' is a really large piece of artillery weighing around 6,000 pounds or 3 tons. So why do they call it a '17 pounder'? Because that is the nominal weight of the projectile it fires. Which really makes no sense at all. Until we back up a couple of centuries and then it really comes into its own:
Back in the days of sailing ships, when Britain was 'The Mistress of the Seas', one way to measure the power of an entire ship was to multiple the size of the cannon shot by the number of cannon that could be fired on one side of that ship (called 'a broadside'). So if a frigate had, say, 50 cannons, and they were 18 pounders, that ship was capable of a '900 pound broadside'. This was really useful information that could be used to quickly layout which ships should engage which enemy ships with the idea of equaling or better, overwhelming each one of them.
As time moved forward, and 'cannon' became breech loading artillery, and 'cannon balls' became specialized artillery shells, the British carried this general type of measurement forward. All fine and well but it does not fit in well with the rest of the world and ends up one of those things that is only obvious to those actually involved. For example, in North Africa in 1943, what would the Brits. use to engage, say, a Tiger tank with an 88mm main gun? Why a 17 pounder, of course (which is really either a 3 inch or a 76.2 mm high velocity artillery piece) because a 6 pounder would not reliably penetrate a Tiger's armor.
Brian
