South Korea helps look for lost North Korean Ship and Crew despite North Korea’s Belligerence

Posted by PITHOCRATES - April 5th, 2014

Week in Review

North Korea is a pain in the ass.  The ruling regime, that is.  Not the people.  Who are always suffering at the hands of the ruling regime.  Which is always looking to cause trouble.  So they can get some international relief for their horrible economy.  As they cannot feed their people or produce enough electricity to light up the night.  So they are always doing something belligerent.  To frighten everyone that they might do something nuclear.  The world gets frightened.  And offers some relief.  It’s the same thing over and over again.  Like I said, they’re a pain in the ass.  Yet despite this when a North Korean ship goes missing South Korea doesn’t hesitate to come to the aid of the belligerent North Korea (see South Korea says 2 NKorean ship crew members dead by AP posted 4/3/2014 on Yahoo! News).

The bodies of two North Korean sailors were recovered Friday after their cargo ship went missing off the southern coast of South Korea but 11 others are still missing, South Korea’s coast guard said…

The statement said the 4,300-ton-class ship carrying iron ore was sailing to China from the North Korean port city of Chongjin.

The coast guard said it had mobilized 13 vessels and six aircraft to search for the ship and its crew members. High waves and a strong wind are still hampering rescue operations, according to coast guard officers.

It was not immediately known how South Korea will handle the rescued North Korean sailors, though Seoul usually repatriates North Korean sailors found drifting in South Korean waters if they want to return home.

The Korean Peninsula remains in a technical state of war as the 1950-53 Korean War ended with an armistice, not a peace treaty. On Monday, the rival Koreas fired hundreds of artillery shells into each other’s waters in a flare-up of animosities.

You see, South Korea is not an ass like North Korea.  Despite their history.  North Korea invaded South Korea. When the UN forces pushed them back to the Yalu River (the border between North Korea and China) Chinese troops poured over the border and extended the Korean War for years.  To this day China is the only friend North Korea has.  Yet here is South Korea helping to find missing North Korean sailors.  Even though that ship was carrying iron ore to China.  If a South Korean ship disappeared off the coast of North Korea would North Korea even lift a finger to help find the ship?  Probably not.  They would likely just patrol their coastline and arrest anyone that comes ashore as a spy.  And use them as bargaining chips for more relief.

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Sounding the Depth, Sea Marks and Bridge Lights

Posted by PITHOCRATES - December 11th, 2013

Technology 101

It’s Important to know both the Depth of the Water beneath you and the Hidden Dangers below the Surface

On November 10, 1975, the Great Lakes bulk ore carrier S.S. Edmund Fitzgerald sank in a powerful Lake Superior storm.  Waves of 35 feet crashed green water across her deck.  But time and again she bobbed back up from under the waves.  Until she began to lose her buoyancy.  No one knows for sure what happened but the Fitzgerald was taking on water prior to her sinking.  One theory said that she bottomed out on Six Fathom Shoal off of Caribou Island.  As she fell into the trough between two huge waves.

A fathom is 6 feet.  So six fathoms would be 36 feet.  Though the water over Six Fathom Shoal could be as shallow as 26 feet.  Which is pretty deep.  But is dangerously shallow for a ship like the Fitzgerald.  For she had a draft of 25 feet.  At best she had 11 feet (36-25) of clearance between the shoal and her hull.  Or in the worst case, 1 foot (26-25).  With the gale force winds pushing the waves as high as 35 feet that would put the trough approximately 17.5 feet (35/2) below the ‘calm’ surface level of the lake.  Which would bring the top of the shoal above the hull of the Fitzgerald.  Thus making a strong case that she bottomed out and fractured her hull and began to take on water.

The theory continues that as she took on water she settled deeper and deeper into the water.  Growing heavier.  And less buoyant.  Until a wall of water swept across her that was too great for her to shake off.  Sending her to the bottom of Lake Superior so quickly that the propeller was still spinning when the bow hit bottom.  Causing the hull to break.  With the torque of the spinning shaft rotating the stern over until she rested hull-up on the bottom.  This is only one theory of many.  People still debate the ultimate cause of her sinking.  But this theory shows the importance of knowing the depth of the water beneath you.  And the great danger of unseen objects below the surface of the water.

Ships use Sea Marks to guide them Safely through Navigable Channels

Those mariners who first crossed the oceans were some of the bravest ever to live.  For if a ship sank in the middle of the ocean chances are people never saw those sailors again.  For there’s nothing to sustain life in the middle of the ocean.  Everything you ate or drank you brought with you.  And crossed at the greatest speed possible to get to your destination before your supplies ran out.  Which was easy to do in the deep waters of the middle of the ocean.  But very dangerous when the water grew shallower.  As you approached land.  Especially for the first time.

If a ship struck a submerged object it could break up the hull and sink the ship.  Especially if you hit it at speed.  This is why they had lookouts high up in the crow’s nest looking for land.  Or indications that the water was growing more shallow.  And they would ‘heave the lead’.  Big burly men (leadsmen) would throw a lead weight on a rope as far out in front of the ship as possible.  Once the lead hit bottom they’d pull it up.  Counting the knots in the rope spaced at 6-foot intervals.  Or fathoms.  Sounding the depth of the water beneath them.  As the sea bottom raced up to the water’s surface they furled their sails to catch less wind.  And slow down.  As they approached land they would approach only so far.  And safely anchor in a safe depth of water near a promising location for a harbor.  Some sailors would then board a dinghy and row into the shallow waters.  Sounding the depth.  And making a chart.  Looking for a safe channel to navigate.  And a place suitable to build a deep-water dock.  Deep enough to sail in to and moor the large sailing vessels that would sail to and from these new lands.

Of course, we could do none of this during the night.  It may be safe to sail in the middle of the ocean at night but it is very dangerous in the shallow waters around land.  At least, for the first time.  After they built a harbor they may build a lighthouse.  A tall building with a beacon.  To guide ships to the new harbor in the dark.  And even add a fog horn to guide ships in when fog obscures the light.  This would bring ships towards the harbor.  But they needed other navigational aids to guide them through a safe channel to the dock.  As time passed we made our navigational aids more advanced.  As well as our ships.  Today a ship can enter a harbor or river in the black of night safely.  Thanks to sea marks.

If Ships wander just Inches off their Course the Results can be Catastrophic

Landmarks are navigational aids on land.  Such as a lighthouse.  While a sea mark is a navigational aid in the water.  Typically a buoy.  A buoyant vessel that floats in the water.  But held in place.  Typically with a chain running from the bottom of the buoy to an anchorage driven into the bottom of the water channel.  Holding it in place to mark the edge of the navigable channel.  In North America we use the colors green and red to mark the channel.  With the “3R” rule “Red Right Returning.”  Meaning a ship returning from a larger body of water to a smaller body of water (and ultimately to a dock) would see red on their right (starboard).  And green on their left (port).  If you’re leaving dock and heading to open water the colors would be the reverse.

As ships move up river the safe channel narrows.  And there are bridges to contend with.  Which compounds the problem of shallow waters.  Fixed bridges will have red lights on piers rising out of the water.  And a green light over the center of the safe channel.  A vertical lift span bridge or a double leaf (lift) bascule bridge will have red lights at either end.  And red lights over the center of the channel when these bridges are closed.  When the center span on a lift bridge is open there will be a green light marking the center of the channel on the lifted center span.  Showing the center of the channel and the safe height of passage.  When the bascule bridge is open there will be a green light on the tip of each open leaf.  Showing the outer edges of the safe channel.

Ships are massive.  And massive things moving have great momentum (mass multiplied by velocity).  The bigger they are and the faster they go the harder it is to stop them.  Or to turn them.  Which means if they wander out of that safe channel they will probably hit something.  And cause great damage.  Either to the ship.  Or to the fixed structures along the waterway.  Like on an Alabaman night.  When a river barge made a wrong turn in poor visibility and entered an un-navigable channel.  Striking a rail bridge.  Pushing the bridge out of alignment.  But not enough to break the welded rail.  Which left the railroad block signal green.  Indicating the track was clear ahead.  The river pilot thought that one of the barges had only run aground.  And was oblivious to what he did.  And when Amtrak’s Sunset Limited sped through and hit that kink in the track it derailed.  Killing 47 people.  About twice the loss of life when the Fitzgerald sank.  Showing the importance of navigation charts, sea marks and bridge lights.  For if ships wander just inches off their course the results can be catastrophic.

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Trucks, Trains, Ships and Planes

Posted by PITHOCRATES - August 21st, 2013

Technology 101

Big Over-the-Road Tractor Trailer Trucks have Big Wheels so they can have Big Brakes

If you buy a big boat chances are you have a truck or a big SUV to pull it.  For rarely do you see a small car pulling a large boat.  Have you ever wondered why?  A small car can easily pull a large boat on a level (or a near level) surface.  That’s not the problem.  The problem is stopping once it gets moving.  For that is a lot of mass.  Creating a lot of kinetic energy (one half of the mass times velocity squared).  Which is dissipated as heat as brake shoes or pads rub against the wheels.  This is why you need a big truck or SUV to pull a boat.  So you can stop it once it gets moving.

Big trucks and big SUVs have big wheels and big brakes.  Large areas where brake pads/shoes press against a rotating wheel.  All of which is heavy duty equipment.  That can grab onto to those wheels and slow them down.  Converting that kinetic energy into heat.  This is why the big over-the-road tractor trailer trucks have big wheels.  So they can have big enough brakes to stop that huge mass once it gets moving.  Without the brakes turning white hot and melting.  Properly equipped trucks can carry great loads.  Moving freight safely across our highways and byways.  But there is a limit to what they can carry.  Too much weight spread between too few axles will pound the road apart.  Which is why the state police weighs our trucks.  To make sure they have enough axles supporting the load they’re carrying.  So they don’t break up our roads.  And that they can safely stop.

It’s a little different with trains.  All train cars have a fixed number of axles.  But you will notice the size of the cars differ.  Big oversized boxcars carry a lot of freight.  But it’s more big than heavy.  Heavy freight, on the other hand, like coal, you will see in smaller cars.  So the weight they carry doesn’t exceed the permissible weight/axle.  If you ever sat at a railroad crossing as a train passed you’ve probably noticed that the rail moves as the train travels across.  Watch a section of rail the next time you’re stopped by a train.  And you will see the rail sink a little beneath the axle as it passes over.

If a Ship is Watertight and Properly Balanced it can be covered in Green Water and Rise back to the Surface

So the various sizes of train cars (i.e., rolling stock) keeps each car from being overloaded.  Unlike a truck.  Steel haulers and gravel trains (i.e., dump trucks) have numerous axles beneath the load they’re carrying.  But these axles are retractable.  For the more wheels in contact with the road the more fuel is needed to overcome the friction between the tires and the road.  And the more tires in contact with the road the more tire wear there is.  Tires and fuel are expensive.  So truckers like to have as few tires in contact with the road as possible.  When they’re running empty they will have as many of these wheels retracted up as possible.  Something you can’t do with a train.

That said, a train’s weight is critical for the safe operation of a train.  In particular, stopping a train.  The longer a train is the more distance it takes to stop.  It is hard to overload a particular car in the string of cars (i.e., consist) but the total weight tells engineers how fast they can go.  How much they must slow down for curves.  How much distance they need to bring a train to a stop.  And how many handbrakes to set to keep the train from rolling away after the pressure bleeds out of the train line (i.e., the air brakes).  You do this right and it’s safe sailing over the rails.  Ships, on the other hand, have other concerns when it comes to weight.

Ships float.  Because of buoyancy.  The weight of the load presses down on the water while the surface of the water presses back against the ship.  But where you place that weight in a ship makes a big difference.  For a ship needs to maintain a certain amount of freeboard.  The distance between the surface of the water and the deck.  Waves toss ships up and down.  At best you just want water spray splashing onto your deck.  At worst you get solid water (i.e., green water).  If a ship is watertight and properly balanced it can be covered in green water and rise back to the surface.  But if a ship is loaded improperly and lists to one side or is low in the bow it reduces freeboard.  Increases green water.  And makes it less likely to be able to safely weather bad seas.  The SS Edmund Fitzgerald sank in 1975 while crossing Lake Superior in one of the worst storms ever.  She was taking on water.  Increasing her weight and lowering her into the water.  Losing freeboard.  Had increasing amounts of green water across her deck.  To the point that a couple of monster waves crashed over her and submerged her and she never returned to the surface.  It happened so fast that the crew was unable to give out a distress signal.  And as she disappeared below the surface her engine was still turning the propeller.  Driving her into the bottom of the lake.  Breaking the ship in two.  And the torque of the spinning propeller twisting the stern upside down.

Airplanes are the only Mode of Transportation that has two Systems to Carry their Load

One of the worst maritime disasters on the Great Lakes was the sinking of the SS Eastland.  Resulting in the largest loss of life in a shipwreck on the Great Lakes.  In total 844 passengers and crew died.  Was this in a storm like the SS Edmund Fitzgerald?  No.  The SS Eastland was tied to the dock on the Chicago River.  The passengers all went over to one side of the ship.  And the mass of people on one side of the ship caused the ship to capsize.  While tied to the dock.  On the Chicago River.  Because of this shift in weight.  Which can have catastrophic results.  As it can on airplanes.  There’s a sad YouTube video of a cargo 747 taking off.  You then see the nose go up and the plane fall out of the sky.  Probably because the weight slid backwards in the plane.  Shifting the center of gravity.  Causing the nose of the plane to pitch up.  Which disrupted the airflow over the wings.  Causing them to stall.  And with no lift the plane just fell out of the sky.

Airplanes are unique in one way.  They are the only mode of transportation that has two systems to carry their weight.  On the ground the landing gear carries the load.  In the air the wings carry the load.  Which makes taking off and landing the most dangerous parts of flying.  Because a plane has to accelerate rapidly down the runway so the wings begin producing lift.  Once they do the weight of the aircraft begins to transfer from the landing gear to the wings.  Allowing greater speeds.  However, if something goes wrong that interferes with the wings producing lift the wings will be unable to carry the weight of the plane.  And it will fall out of the sky.  Back onto the landing gear.  But once the plane leaves the runway there is nothing the landing gear can gently settle on.  And with no altitude to turn or to glide back to a runway the plane will fall out of the sky wherever it is.  Often with catastrophic results.

A plane has a lot of mass.  And a lot of velocity.  Giving it great kinetic energy.  It takes long runways to travel fast enough to transfer the weight of the aircraft from the landing gear to the wings.  And it takes a long, shallow approach to land an airplane.  So the wheels touch down gently while slowly picking up the weight of the aircraft as the wings lose lift.  And it takes a long runway to slow the plane down to a stop.  Using reverse thrusters to convert that kinetic energy into heat.  Sometimes even running out of runway before bringing the plane to a stop.  No other mode of transportation has this additional complication of travelling.  Transferring the weight from one system to another.  The most dangerous part of flying.  Yet despite this very dangerous transformation flying is the safest mode of traveling.  Because the majority of flying is up in the air in miles of emptiness.  Where if something happens a skilled pilot has time to regain control of the aircraft.  And bring it down safely.

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Poling, Paddling, Oarlock, Oar, the Galley, Sail, Square-Rig, Lateen-Rig and the Carrack

Posted by PITHOCRATES - August 14th, 2013

Technology 101

(Originally published January 11th, 2012)

The Modern Container Ship is Powered by Diesel Engines making Ocean Crossings Safe, Reliable and Efficient

Trade required a way to move heavy things in large quantities.  Railroads do a pretty good job of this.  Ever get stopped by a mile long train with double-stack containers?  These are the hot-shot freights.  They get the right-of-way.  Other trains pull aside for them.  And they get the best go-power.  They lash up the newest locomotives to these long freights.  Carrying containers full of expensive treasures like plasma televisions, smartphones, computers, clothing, perfume, cameras, etc.  Unloaded from great container ships days earlier.  And hustled out of these great container seaports to cities across the U.S.

These goods came into the country the way goods have for millennium.  On a ship.  Because when it comes to transporting large cargoes there is no more cost efficient way than by ship.  It’s slow.  Unlike a train.  But it can carry a lot.  Which really reduces the cost of shipping per unit shipped.  Keeping sale prices low.  And profits high.

Diesel engines power the modern container ship.  That either turn a propeller directly.  Or by turning an electric generator.  Which in turn powers an electric motor that turns a propeller.  Makes crossing the oceans pretty much a sure thing these days.  And timely.  Day or night.  Wind or no wind.  With the current.  Or against the current.  But travel on water was not always this safe.  Reliable.  Or efficient.

Galleys were Fast and Maneuverable but Decks full of Rowers left Little Room for Cargo

Earliest means of marine propulsion was a man using a pole.  Standing in a boat with his cargo, he would stick the pole through the water and into the riverbed.  And push.  The riverbed wouldn’t move.  So he would.  And the boat he was standing in.  A man kneeling in a canoe could propel the canoe forward with a paddle.  By reaching forward, dipping the paddle into the water and pulling.  By these strokes he would propel himself forward.  And the canoe he was kneeling in.  We transfer the force of both poling and paddling to the vessel via the man-vessel connection.  The feet.  The knees.  Or, if sitting, the butt.  A useful means of propulsion.  But limited by the strength of the man poling/paddling.

The oarlock changed that.  By adding leverage.  Which was a way to amplify a man’s strength.  An oar differs from a paddle because we attach it to the boat.  In an oarlock.  A pivot point.  An oar is similar to a paddle but longer.  It attaches to the oarlock so that a short length of it extends into the boat while a longer length extends outside of the boat.  The rower then rows.  Facing backwards to the boat’s direction.  His short stroke inside the boat transfers into a longer stroke outside of the boat (the leverage).  And the attachment point allows the rower to use both hands, arms and legs.  He pulls with his arms and pushes with his legs.  The force is transferred through the oarlock and pushes the boat forward.  So a single stroke from an oar pulled a boat much harder than a single stroke of a paddle.  And allowed more rowers to be added.  We call these multiple-oared boats galleys.  Such as the Viking longship.  With up to 10 oars on a side.  Or the Phoenician bireme which had two decks of rowers.  Or the Greek trireme which had three decks of rowers.  Or the Carthaginian/Roman quinquereme which had five decks of rowers.

Of course, decks full of rowers left little room for cargo.  Which is why these ships tended to be warships.  Because they could maneuver fast.  Another means of propulsion was available, though.  Wind.  It had drawbacks.  It didn’t have the quick maneuverability as a galley.  And you couldn’t just go where you want.  The prevailing winds had a large say in where you were sailing to.  But without rowers you had a lot more room for cargo.  And that was the name of the game when it came to international trade.

The Carrack opened the Spice Trade to the European Powers and Kicked Off the Age of Discovery

Our first civilizations used sailing ships.  The Sumerians.  And the Egyptians.  The Egyptians used a combination of sail and oars on the Nile.  Where the winds and current were pretty much constant.  They used wind-power to sail upstream.  And oared downstream.  Both the Egyptians and Sumerians used sail to reach India.  The Phoenicians, Greeks and Romans used sail to ply the Mediterranean.  Typically a single square sail on a single mast perpendicular to the keel.  Then later the triangular lateen parallel to the keel.  A square-rig square sail worked well when the wind was behind you.  While the lateen-rig could sail across the wind. And closer into the wind.

The wind blew a square-rig forward.  Whereas the wind pushed and pulled a lateen-rig forward by redirecting the wind.  The lateen sail split the airstream.  The sail redirects the wind towards the stern, pushing the boat forward.  The wind going over the outside of the sail curved around the surface of the sail.  Creating lift.  Like an airplane wing.  Pulling the boat forward.

It was about this time that Europeans were venturing farther out into the oceans.  And they did this by building ships that combined these sails.  The square rigging allowed them to catch the prevailing winds of the oceans.  And lateen rigging allowed them to sail across the wind.  One of the first ships to combine these types of sails was the carrack.  The Portuguese first put the carrack to sea.  The Spanish soon followed.  Christopher Columbus discovered The Bahamas in a carrack.  Vasco da Gama sailed around Africa and on to India in a carrack.  And Ferdinand Magellan first sailed around the world in a carrack (though Magellan and his other four ships didn’t survive the journey).  It was the carrack that opened the spice trade to the European powers.  Beginning the age of discovery.  And European colonialism.

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Celestial Navigation, Insurance and the Joint Stock Company

Posted by PITHOCRATES - July 10th, 2013

Technology 101

(Originally published November 30th, 2011)

Despite Precise Celestial Navigation a lot of Ships and Valuable Cargoes still got Lost at Sea

Open sea navigation was once very perilous.  It took a long time before ships ventured from sight of the shoreline.  And a lot of technology.  Boats used to go the long way across the Mediterranean Sea.  Because being in open water at night without any visible landmarks was very dangerous.  So they hugged the coastline.  Adding days to every voyage.  And more danger.  Because the longer at sea the greater the risk there was of sinking.  Especially when you were skirting the rock-infested shallows of the shoreline.

The Sumerians charted the stars.  The Greeks continued this work, producing charts that could tell you what latitude (north/south position) you were at by looking at the stars and planets.  By measuring the angle of the stars and planets above the horizon.  The Arabs created one of the first tools to measure these angles.  The kamal.  Knowing this angle you could do a little math and look at a pre-calculated table of values.  And get your latitude.  Better instruments followed.  The cross-staff.  The astrolabe.   And then the sextant.  The gold standard of angle measuring until the advent of Global Positioning Satellites (GPS).  Calculating longitude (east/west position) was a bit more complicated.  Because the earth rotated.  Which required some more skillful measuring and more calculations.  And/or a reliable and accurate clock.  To adjust your results by the time of day.  As the time as well as the stars moved from east to west as the planet rotated.

The Chinese developed the magnetic compass.  A helmsman steered his ship by the compass.  The navigator checked the angles of celestial bodies (sun, moon, stars and planets), checked time and the ship’s speed to fix the ship’s position.  By determining latitude and longitude.  The navigator fed course headings and course corrections to the helmsman.  Armed with these skills, tools, celestial charts and tables, the navigator could do a little math and navigate a ship across a vast ocean day or night to any port in the world.  Transporting valuable cargoes safely and timely across the globe.  Pretty impressive for the time.  But despite this precise celestial navigation, a lot of ships still got lost at sea.  As well as their valuable cargoes.

The Joint-Stock Company and Insurance Reduced the High Risks of Transoceanic Shipping

No matter how well a navigator could fix a ship’s position there were some things he just couldn’t do.  Such as avoid an uncharted reef.  Prevent a mutiny.  Fend off pirates.  Fend off enemy warships.  Make storms go away.  Or even see through dense fog.  Simply put being on a small wooden ship in the middle of an ocean was very dangerous.  Which poised quite the problem for early global trade.

It was a huge investment to put a ship to sea.  It took another huge investment to fill a ship with valuable cargo.  And if that ship didn’t make it back to sell that cargo it was very bad news for the investor.  A lost ship could financially ruin them.  So not only could you get rich in this new global trade you could become impoverished.  Which made rich people reluctant to finance this early trade.  Because it was so risky.  Two things helped to reduce this risk to manageable levels.  Insurance.  And the joint-stock company.

A group of investors could buy stock into a company that was going to make numerous voyages on various ships.  In exchange for a share of the profits from this trade each investor paid a share of its cost.  Thus the joint-stock company spread the risk to multiple investors, reducing the risk to any one person.  So one lost ship would not cause financial ruin to any one investor.  Thus encouraging investment into this lucrative new trade of transoceanic shipping.  And with the advent of insurance, shippers could insure each voyage for a small affordable fee.  By collecting this small fee on every voyage the insurer could pay for the few ships and cargoes lost at sea.  Not the investors.  Thus further encouraging investment into this very risky endeavor.

Celestial Navigation, Insurance and the Joint-Stock Company made Transoceanic Shipping Possible

The smartphone you can’t live without today most likely came to you via a large container ship from a port across some ocean.  It made a long and perilous voyage to get to you.  Which wouldn’t have been possible without celestial navigation, insurance and the joint-stock company.  The things that made transoceanic shipping possible.  Most of which are still in use today.  As they were when brave mariners took to the open seas in those small wooden ships of yesteryear.

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Flat-Bottomed Boat, Keel, Standing Rigging, Chinese Junk, Daggerboard, Balanced Rudder, Compartment and Junk Rig

Posted by PITHOCRATES - May 16th, 2012

Technology 101

Typical River Transport has a Flat Bottom and a Shallow Draft with Little Freeboard

What do most of the oldest and greatest cities in the world have in common?  Madrid.  Lisbon.  Paris.  London.  Amsterdam.  Belgrade.  Vienna.  Rome.  Cairo.  Kiev.  Moscow.  Baghdad.  New Delhi.  Shanghai.  Ho Chi Minh City.  Bangkok.  Hong Kong.  São Paul.  Buenos Aires.  Santiago.  Quebec City.  Montreal.  Detroit.  Boston.  New York.  Philadelphia.  Pittsburgh.  What do these cities have in common?  Rivers.  Coastal water.  Or safe harbors on the oceans.

Why is this?  Is it because their founders liked a good view?  That’s why people today pay a premium to live on the water’s edge.  But back then it was more necessity than view.  These were times before railroads.  Even before roads connected these new cities.  Back then there was only one way to transport things.  On the water.  And rivers were the early highways that connected the cities.  Which is why we built our cities on these rivers.  To transport the food or raw materials a city produced.  And to transport to these cities the things they needed to survive and grow.  And some of the earliest river transports were flat-bottomed boats.  Like the scow.  Punt.  Sampan.  And the barge.

Rivers are calm compared to the oceans.  Which allows a different boat design.  River transport doesn’t have to be sturdy to withstand rolling waves and high winds.  Which allows the design to focus on the main purpose of a boat.  Hauling freight.  Typical river transport has a flat bottom.  A shallow draft with little freeboard (i.e., sitting very low in the water with the top deck very close to the surface of the water).  And a square bow.  This allows these boats to operate in shallow waters.  Allowing them to run up right onto a river landing or beach.  Where they can be easily loaded with their cargoes.  Or unloaded.  And their flat, rectangular shapes maximize the cargo they can carry.  Propulsion is simple.  A man can push a small boat along with a pole.  Animal power can pull larger barges.  Or, later, motors were able to power them.  Or a tugboat could pull or push them.

The Chinese Junk had a Flat Bottom with no Keel allowing them to Carry a Lot of Cargo

These flat-bottomed boats are great for hauling freight.  But they are not very seaworthy.  Because the ocean’s waves will toss around any boat with a shallow draft and little freeboard.  Breaking it up and sending it and its cargo to the bottom of the ocean.  Which has confined these to the calm of rivers, bays and coastal waterways.  Cargoes that have to travel further than these allow are loaded onto an ocean-going vessel with a deeper draft.  And a higher freeboard.  With a keel.  That can withstand the leeward force of the wind.  So instead of being pushed sideways (or simply rolling over) the keel allows those sideway winds to fill a sail and propel a ship forward.  By sticking deeper into the water.  So as the wind tries to push the boat sideways the large amount of water in contact with the keel pushes back against that leeward force.  Allowing it to sail across the wind.

But there is a tradeoff.  The curved sections of the hull that form the keel reduces the amount of cargo a ship can carry in its hull.  Also, these ocean-going vessels have a lot of sail.  And a lot of rigging to hold it in place.  Standing rigging.  While the sails required running rigging.  To raise and lower sails depending on the wind conditions.  Which takes up space that can’t be used for cargo.  And requires a lot of sailors.  In fact, much of the upper deck is full of rigging and sailors instead of cargo.  But this was the tradeoff to sail into the rougher waters of the ocean.  You had to sacrifice revenue-earning cargo.  But there was one ship design that brought together the benefits of the flat-bottomed river scow and the ocean-going fully rigged sailing ship.  The Chinese junk.

The Chinese junk dates as far back as the 3rd century BC.  And began crossing oceans as early as the second century AD.  Long before the Europeans ventured out in their Age of Discovery.  The junk has a flat bottom with no keel.  But a high freeboard.  Which lets it carry a lot of cargo.  And operate in shallower waters than a fully rigged sailing ship.  But it could also sail in the rougher seas of the ocean.  When it did it lowered a daggerboard.  A centerboard that can lower from a watertight trunk within the hull into the water to act like a keel.  To resist those leeward forces.  Often installed forward in the hull so as not to take up valuable cargo space in the center of the ship.  Because they mount this forward the leeward forces could cause the back end of the ship to torque around the daggerboard. To counteract this force they use an oversized rudder on the stern.  To balance the resistance to those leeward forces.  Because the rudder was so large and had to deflect a lot of water it was difficult to turn.  Taking a team of men to operate it.   To help turn such a large rudder they developed ‘powered’ steering.  With a balanced rudder.  The axis the rudder turned on was just behind the leading edge of the rudder.  So when they turned the rudder the water hitting the part in front of the turning axis helped turn the rudder in the direction the crew was trying to turn it.  So the large rudder area past the turning axis could deflect the large volume of water necessary to turn the ship.

The Chinese gave us Papermaking, Printing, the Compass and Gunpowder but the Europeans Conquered the World

So the junk could travel in the shallow waters of harbors and rivers.  And the deep water of the ocean.  It was the first ship to compartmentalize the hull.  Making it very seaworthy.  Especially if it struck bottom and punched a hole in the hull.  Because of the compartments the flooding was contained to the one compartment.  Allowing the ship to remain afloat.  A design all ships use today.  The junk also used a different sailing rig.  The junk rig.  It’s low tech.  Was inexpensive.  And required smaller crews.

A three-mast junk has three masts.  And three sails.  One sail per mast.  And the masts are free standing.  They don’t need any standing rigging to hold them in place.  Because they don’t carry heavy loads of running rigging and sailors.  The sail is stretched between a yard and a boom.  The yard is at the top.  The boom is along the bottom.  Between the yard and the boom battens give the sail strength and attach it to the mast.  Think of a batten as that stick in the bottom of a window shade.  Grabbing this batten allows you to apply an even force on that window shade when pulling it down.  If this stick wasn’t there and you pulled down on the window shade the uneven forces across the shade would tear it.  Same principle on a junk rig.  Which allows them to use less expensive sail material.  To raise this sail up the mast you pulled up the yard via a block and tackle at the top of the mast.  From the deck.  With fewer crew members.  The sail is attached to the mast near one edge.  It’s pivoted to catch and redirect wind to the stern.  Propelling the ship forward.  And the battens will bend in strong enough winds to curve the sail.  Creating lift on the other side of the sail to pull the ship forward.

The Chinese gave us papermaking, printing, the compass and gunpowder.  But it was the Europeans that used these inventions to conquer the world.  For the Chinese had no interest in civilizations outside of China.  For when you had the best, they thought, what was the point?  So the Europeans came to them.  Even took Hong Kong from them.  When it was the Chinese that could have had the technologically advanced civilization.  An army fielding muskets and cannon.  And a navy of junk warships that could have gone anywhere the Europeans could have gone.  And farther.  Into the shallow waters and up the rivers where the European warships could not go.  They could have sailed up the Thames to London.  Up the Seine to Paris.  Even into Amsterdam.  Home of the Dutch East India Company.  That took such a great interest in all those Asian goods in the first place.   That brought the British to China to compete against the Dutch.  Leading to the Opium Wars.  And the loss of Hong Kong.  Imagine how different the world would be had China embraced their technology.  Like they are today.  Perhaps we will soon see the answer to that great ‘what if’ question.

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Poling, Paddling, Oarlock, Oar, the Galley, Sail, Square-Rig, Lateen-Rig and the Carrack

Posted by PITHOCRATES - January 11th, 2012

Technology 101

The Modern Container Ship is Powered by Diesel Engines making Ocean Crossings Safe, Reliable and Efficient

Trade required a way to move heavy things in large quantities.  Railroads do a pretty good job of this.  Ever get stopped by a mile long train with double-stack containers?  These are the hot-shot freights.  They get the right-of-way.  Other trains pull aside for them.  And they get the best go-power.  They lash up the newest locomotives to these long freights.  Carrying containers full of expensive treasures like plasma televisions, smartphones, computers, clothing, perfume, cameras, etc.  Unloaded from great container ships days earlier.  And hustled out of these great container seaports to cities across the U.S.

These goods came into the country the way goods have for millennium.  On a ship.  Because when it comes to transporting large cargoes there is no more cost efficient way than by ship.  It’s slow.  Unlike a train.  But it can carry a lot.  Which really reduces the cost of shipping per unit shipped.  Keeping sale prices low.  And profits high.

Diesel engines power the modern container ship.  That either turn a propeller directly.  Or by turning an electric generator.  Which in turn powers an electric motor that turns a propeller.  Makes crossing the oceans pretty much a sure thing these days.  And timely.  Day or night.  Wind or no wind.  With the current.  Or against the current.  But travel on water was not always this safe.  Reliable.  Or efficient.

Galleys were Fast and Maneuverable but Decks full of Rowers left Little Room for Cargo

Earliest means of marine propulsion was a man using a pole.  Standing in a boat with his cargo, he would stick the pole through the water and into the riverbed.  And push.  The riverbed wouldn’t move.  So he would.  And the boat he was standing in.  A man kneeling in a canoe could propel the canoe forward with a paddle.  By reaching forward, dipping the paddle into the water and pulling.  By these strokes he would propel himself forward.  And the canoe he was kneeling in.  We transfer the force of both poling and paddling to the vessel via the man-vessel connection.  The feet.  The knees.  Or, if sitting, the butt.  A useful means of propulsion.  But limited by the strength of the man poling/paddling.

The oarlock changed that.  By adding leverage.  Which was a way to amplify a man’s strength.  An oar differs from a paddle because we attach it to the boat.  In an oarlock.  A pivot point.  An oar is similar to a paddle but longer.  It attaches to the oarlock so that a short length of it extends into the boat while a longer length extends outside of the boat.  The rower then rows.  Facing backwards to the boat’s direction.  His short stroke inside the boat transfers into a longer stroke outside of the boat (the leverage).  And the attachment point allows the rower to use both hands, arms and legs.  He pulls with his arms and pushes with his legs.  The force is transferred through the oarlock and pushes the boat forward.  So a single stroke from an oar pulled a boat much harder than a single stroke of a paddle.  And allowed more rowers to be added.  We call these multiple-oared boats galleys.  Such as the Viking longship.  With up to 10 oars on a side.  Or the Phoenician bireme which had two decks of rowers.  Or the Greek trireme which had three decks of rowers.  Or the Carthaginian/Roman quinquereme which had five decks of rowers.

Of course, decks full of rowers left little room for cargo.  Which is why these ships tended to be warships.  Because they could maneuver fast.  Another means of propulsion was available, though.  Wind.  It had drawbacks.  It didn’t have the quick maneuverability as a galley.  And you couldn’t just go where you want.  The prevailing winds had a large say in where you were sailing to.  But without rowers you had a lot more room for cargo.  And that was the name of the game when it came to international trade.

The Carrack opened the Spice Trade to the European Powers and Kicked Off the Age of Discovery

Our first civilizations used sailing ships.  The Sumerians.  And the Egyptians.  The Egyptians used a combination of sail and oars on the Nile.  Where the winds and current were pretty much constant.  They used wind-power to sail upstream.  And oared downstream.  Both the Egyptians and Sumerians used sail to reach India.  The Phoenicians, Greeks and Romans used sail to ply the Mediterranean.  Typically a single square sail on a single mast perpendicular to the keel.  Then later the triangular lateen parallel to the keel.  A square-rig square sail worked well when the wind was behind you.  While the lateen-rig could sail across the wind. And closer into the wind.

The wind blew a square-rig forward.  Whereas the wind pushed and pulled a lateen-rig forward by redirecting the wind.  The lateen sail split the airstream.  The sail redirects the wind towards the stern, pushing the boat forward.  The wind going over the outside of the sail curved around the surface of the sail.  Creating lift.  Like an airplane wing.  Pulling the boat forward.

It was about this time that Europeans were venturing farther out into the oceans.  And they did this by building ships that combined these sails.  The square rigging allowed them to catch the prevailing winds of the oceans.  And lateen rigging allowed them to sail across the wind.  One of the first ships to combine these types of sails was the carrack.  The Portuguese first put the carrack to sea.  The Spanish soon followed.  Christopher Columbus discovered The Bahamas in a carrack.  Vasco da Gama sailed around Africa and on to India in a carrack.  And Ferdinand Magellan first sailed around the world in a carrack (though Magellan and his other four ships didn’t survive the journey).  It was the carrack that opened the spice trade to the European powers.  Beginning the age of discovery.  And European colonialism.

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Celestial Navigation, Insurance and the Joint Stock Company

Posted by PITHOCRATES - November 30th, 2011

Technology 101

Despite Precise Celestial Navigation a lot of Ships and Valuable Cargoes still got Lost at Sea

Open sea navigation was once very perilous.  It took a long time before ships ventured from sight of the shoreline.  And a lot of technology.  Boats used to go the long way across the Mediterranean Sea.  Because being in open water at night without any visible landmarks was very dangerous.  So they hugged the coastline.  Adding days to every voyage.  And more danger.  Because the longer at sea the greater the risk there was of sinking.  Especially when you were skirting the rock-infested shallows of the shoreline.

The Sumerians charted the stars.  The Greeks continued this work, producing charts that could tell you what latitude (north/south position) you were at by looking at the stars and planets.  By measuring the angle of the stars and planets above the horizon.  The Arabs created one of the first tools to measure these angles.  The kamal.  Knowing this angle you could do a little math and look at a pre-calculated table of values.  And get your latitude.  Better instruments followed.  The cross-staff.  The astrolabe.   And then the sextant.  The gold standard of angle measuring until the advent of Global Positioning Satellites (GPS).  Calculating longitude (east/west position) was a bit more complicated.  Because the earth rotated.  Which required some more skillful measuring and more calculations.  And/or a reliable and accurate clock.  To adjust your results by the time of day.  As the time as well as the stars moved from east to west as the planet rotated.

The Chinese developed the magnetic compass.  A helmsman steered his ship by the compass.  The navigator checked the angles of celestial bodies (sun, moon, stars and planets), checked time and the ship’s speed to fix the ship’s position.  By determining latitude and longitude.  The navigator fed course headings and course corrections to the helmsman.  Armed with these skills, tools, celestial charts and tables, the navigator could do a little math and navigate a ship across a vast ocean day or night to any port in the world.  Transporting valuable cargoes safely and timely across the globe.  Pretty impressive for the time.  But despite this precise celestial navigation, a lot of ships still got lost at sea.  As well as their valuable cargoes.

The Joint-Stock Company and Insurance Reduced the High Risks of Transoceanic Shipping

No matter how well a navigator could fix a ship’s position there were some things he just couldn’t do.  Such as avoid an uncharted reef.  Prevent a mutiny.  Fend off pirates.  Fend off enemy warships.  Make storms go away.  Or even see through dense fog.  Simply put being on a small wooden ship in the middle of an ocean was very dangerous.  Which poised quite the problem for early global trade.

It was a huge investment to put a ship to sea.  It took another huge investment to fill a ship with valuable cargo.  And if that ship didn’t make it back to sell that cargo it was very bad news for the investor.  A lost ship could financially ruin them.  So not only could you get rich in this new global trade you could become impoverished.  Which made rich people reluctant to finance this early trade.  Because it was so risky.  Two things helped to reduce this risk to manageable levels.  Insurance.  And the joint-stock company.

A group of investors could buy stock into a company that was going to make numerous voyages on various ships.  In exchange for a share of the profits from this trade each investor paid a share of its cost.  Thus the joint-stock company spread the risk to multiple investors, reducing the risk to any one person.  So one lost ship would not cause financial ruin to any one investor.  Thus encouraging investment into this lucrative new trade of transoceanic shipping.  And with the advent of insurance, shippers could insure each voyage for a small affordable fee.  By collecting this small fee on every voyage the insurer could pay for the few ships and cargoes lost at sea.  Not the investors.  Thus further encouraging investment into this very risky endeavor.

Celestial Navigation, Insurance and the Joint-Stock Company made Transoceanic Shipping Possible

The smartphone you can’t live without today most likely came to you via a large container ship from a port across some ocean.  It made a long and perilous voyage to get to you.  Which wouldn’t have been possible without celestial navigation, insurance and the joint-stock company.  The things that made transoceanic shipping possible.  Most of which are still in use today.  As they were when brave mariners took to the open seas in those small wooden ships of yesteryear.

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