Colonial Policeman

Yes, the Koryetz (Korean) on the beat. She's shown late 19th century with a French courtesy flag at her mainmast.

It's a fairly typical example of a late 19th century colonial gunboat - the sort built to enforce European colonial laws and domination in the 'uncivilised' areas of the world.

The Koryetz and her sisters were built in Denmark from the late 1870s/ late 1880s. She was equipped with two 8" black powder cannon - limited in range - for knocking down native forts and such. She had a shallow enough draft to go up large rivers and a good spread of sail for those times when coal was in short supply. Was she a steamer with auxiliary sails or a sail boat with an auxiliary steam engine? Either way, those hybrids had the same problem when it came to arming them with guns.

The best place for a gun is on the deck with as wide a field of fire as possible. With a sailer, shrouds, stays and ratlines are going to get in the way of your swivel gun or turret. The Koryetz's answer to this problem was to have two and move them outboard on sponsons (a kind of outrigger) This gave each a 180 deg arc, port and starboard, but, of course, they couldn't be used together as firing across the deck will blow away all those shrouds, etc. Therefore, a two gun ship becomes a single gun ship when firing broadside - inefficient.

Firing end on - possible with guns on sponsons - will likely damage your jib stays and other rigging for'ard.

This problem was why the old sailer/ steamers clung to the broadside, ie, short barreled, seried guns firing through traps in the hull. Swivel guns on the maindecks got in the way of all those sails and ropes.

But, short barreled guns, particularly those firing through traps, only had a short range. There was only limited elevation possible - unless you made the traps so large you exposed the crew - so they fired in a flat trajectory.

This worried large colonial powers, such as Britain, because, her ships were needed to cross oceans and therefore, until steam became more reliable and efficient, Royal Navy ships had to carry sails. These constraints didn't bother those countries whose ships only needed to leave the harbour and cruise for a day up the coast. Those vessels didn't have to carry sails and, so, they could afford to place their guns wherever they liked.

Turrets were the obvious choice and, with the breechloader, they could have as big a calibre as could fit on the hull. British yards made a couple of turret ships for the Dutch in the 1860s, that horrified the British Admiralty.

The Dutch ships carried shell guns on revolving turrets (2 guns) that potentially would've happily blown holes in ships like HMS Warrior on the displacement of a harbour tugboat. Unfettered by sails, they relied on steam alone and their uncluttered decks allowed the turret a whopping 230degs of arc.

Unlike Civil War monitors, the Dutch ships were seagoing and, if Britain and Holland had been at war, could've sailed up and down the coast of Britain sinking whatever they chose. Not a pleasant thought for a country dependent on its sea trade.

But Britain had the services of William White - the finest naval architect of his generation. The French had Dupuy de Lome, the Italians, Bernedetto Brin and together they revolutionised the steam warship - more on these later.

Don