types of naval guns requires analysis both by nation and by time period. The types used by different nations at the same time often were very different, even if they were labelled similarly. The types used by a given nation would shift greatly over time, as technology, tactics, and current weapon fashions changed. Some types include: Demi-cannon Culverin Demi-culverin Carronade Paixhans gun In 1712 Colonel Albert Borgard was appointed to the head of the British Royal Ordnance, and introduced a new method of classification by which guns were defined by their pound rating — theoretically, the weight of a single solid iron shot fired by that bore of cannon. Standard sizes were: 42-pounders(7in), 36-pounders(6.7in), 32-pounders(6.4in), 24-pounders(5.5in), 18-pounders(5in), 12-pounders(4.7in), 9-pounders(4in), 8-pounders, 6-pounders(3.5in), and various smaller calibres. French ships used similarly standardized guns of 36-pound, 24-pound, 18-pound, 12-pound, and 8-pound calibers, augmented by carronades and smaller pieces. However, it must be noted that the word "pound" in this context refers to the French pre-metric unit of weight - the livre, which was 7.916 percent more than the English/British equivalent; thus, as an example, the French "36-pounder" actually equated in British terms to 38lb 13.6oz. A similar qualification must be placed on references to size of guns (i.e. weight of projectile) for every other nation, since each country had its own system of weights and measures. The Spanish "pound", or libra, as another example, equated to 0.4608 kg (the British pound equals 0.4536 kg); and thus the Spanish 36-libra projectile actually weighed 36lb 9.143oz in British measurements. In general, larger ships carrying more guns carried larger ones as well. The muzzle-loading design and weight of the iron placed design constraints on the length and size of naval guns. Muzzle-loading required the cannon to be positioned within the hull of the ship for loading. The hull width, guns lining both sides, and hatchways in the centre of the deck also limited the room available. Weight is always a great concern in ship design as it affects speed, stability, and buoyancy. The desire for longer guns for greater range and accuracy, and greater weight of shot for more destructive power, led to some interesting gun designs. Long nine One unique naval gun was the long nine. It was a proportionately longer-barrelled 9-pounder. It was typically mounted as a bow or stern chaser where it was not perpendicular to the keel, and this also allowed room