History of Lines series: the Geometry of Cannon-Fire (1812)

JF Ptak Science Books   Post 2369

There were many integral components to firing a cannon on a ship, not the least of which were the Powder Boys, the small, young, semi-strong kids who would run the gunpowder from a below-decks armory to whatever gun deck was needed.  It was a relatively simple procedure, filling up a longish tube (cannon  derived from the Italian  cannone--or large tube--which came from the Latin canna from the Greek  kannē , meaning something like a reed or any similar hollow thing) with gunpowder and then cannonball/shot and then wad, then causing the gunpowder/propellant to ignite and throw the ball.  Basically, that was it, though you needed to maintain the cannon, aim it, and so on (don't forget to first swab the bore from unexploded gunpowder so you don't blow things up!).

The (first)  image above of found modernist/semi-dadaist artwork comes form 1812 and was found in Rees' Encyclopedic Dictionary from the article on "Shipbuilidng"   and illustrates the ways in which the stern of a ship can be outfitted with cannons--actually, the sterns of the HMS Bodiceae (28 18-pounders)  and HMS Hamadryad  (36 guns). Also by this time cannons had been carried on naval ships for nearly four hundred years, while the first cannons appeared on the ground in Europe another few hundred years before that. 

 

In the third detail (below) we see the coverage of the four cannons placed in the stern of the Bodicae, mainly pointing out its weaknesses, showing the undefended arc, which comprises about 1/3, or about 60 degrees of the defensive posture.  The Hamadryad on the other hand shows 100% coverage of the 180+ degrees of attack possibilities shown, along with secondary and teriary areas of fire coverage covered by more than one gun.

 

A fine,tiny detail from the full engraved sheet:

And the full sheet:

  

This is pretty much all that was needed to fire a cannon, except the men of course.

 

Comments

[Ray Girvan]

This strangely reminds me of "gun kata" - the fictional martial art invented for the movie Equilibrium - that depended strongly on statistical probabilities of where an opponent would be shootable, or conversely not likely to shoot. It certainly seems that the idea that ships in this era relied solely on getting into positions where a 'broadside' could be fired is a gross oversimplification.