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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Prevailing Winds, Channel Markers, Buoys, Portage, Canals, Locks, Niagara Falls and the Welland Canal

Posted by PITHOCRATES - January 30th, 2013

Technology 101

The Lateen-Rigged Sail allows Ships to Maneuver onto the Prevailing Winds Superhighways

Oceans are deep.  Allowing ships to cross them without fear of striking bottom.  Which helped the age of sail.  As sailors could use the prevailing winds to fill large masts of square-rigged sails to blow them across oceans.  Sailing to the New World with the trade winds (near the equator) and polar easterlies (near the poles) filling their sails.  And sailing from the New World with the westerlies (in the middle latitudes in both hemispheres) filling their sails.  The deep oceans let these sailing vessels move unrestricted to find the best wind.

That is, once these sailing vessels got to the proper latitude.  Getting there they had to use another kind of sail.  A lateen-rigged sail.  A triangular sail with a leading edge that cut into the wind.  Splitting the wind so part of it filled the sail.  The sail blew out and redirected the wind to the stern of the ship.  While the wind passing over the top of the curved sail created lift.  Like on an aircraft wing.  Pulling the ship forward.  This allows a wind blowing in from the side of a ship to propel it forward.  Which allows a sailing vessel to sail into the wind.  By sailing in a zigzag path.  Or beating.  After sailing in one direction they come about.  Or tack.  Turning the bow through the wind so it blows in from the other side of the ship.

The wide open and deep oceans let these sailing vessels maneuver at will to catch the wind.  Propelling them forward at speed.  Without fear of grounding out on the bottom.  Taking them to the great superhighways across the oceans.  To the trade winds and polar easterlies to sail west.  And to the westerlies to sail east.  Where these winds could fill multiple squared-rigged sails on a single mast.  On ships with multiple masts.  Allowing them to catch a lot of wind.  And to drive them forward to their destination.

Channel Markers and Buoys are Color-Coded telling Ship Captains ‘Red Right Returning’

Of course it’s these destinations that really matter.  For sailing around in the middle of the ocean is worthless unless you can load and unload cargo somewhere.  Getting to these ports was a little trickier.  Because it required sailing closer to land.  Where the ocean floor rises up quickly from great depths.  Making sailing near shores hazardous.  As hidden shoals and reefs hide just below the surface.  Threatening to cut a deep gash in a ship’s hull.  Or a ship could run aground in the shallows.  Where they may have to wait for a rising tide to free them.  All the while risking being damaged by any storm that blew in.

The first sailors who arrived in the New World had no navigational aids like we do today.  Often having to rely on the experience of a grizzled captain who could see and smell dangers in the water.  Or they dropped anchor away from the shore and explored the coast in smaller boats to sound out sea approaches to a deep-water harbor.  As time passed lighthouses dotted the shoreline.  And other navigational aids guided ship captains.  To warn them of dangerous waters.  And show safe channels to navigate.    Channel markers and buoys are color-coded.  With paint for day navigation.  And lights for night navigation.  In the New World (and Japan, South Korea and the Philippines) the colors are red and green.  When entering a harbor or river from the sea the red is kept on the right of a ship.  Mariners learn this with the memory device ‘red right returning’.

When the French sailed up the Saint Lawrence River they founded the oldest walled-city in North America.  Quebec City.  They then sailed as far upstream as they could.  Founding the city of Montreal.  Going beyond Montreal required portaging around the rapids at Montreal.  And a few others until they got to Lake Ontario.  Where they could re-embark ships and sail across Lake Ontario and into the Niagara River.  Where they had to portage around the rapids.  And Niagara Falls.  Where they once again could re-embark ships and enter Lake Erie.  Then sail up the Detroit River.  Across Lake St. Clair.  Up the St. Clair River.  And into Lake Huron.  Where they could sail through the Straits of Mackinac and into Lake Michigan.  Or up the St. Marys River.  Where they could portage around the rapids in the St. Marys River.  Reentering the river upstream of the rapids to let them sail into Lake Superior.  Where they could sail all the way to Minnesota.  And take on iron ore.  Mined from the great iron ore deposits beyond Lake Superior.  To feed the blast furnaces of America’s steel industry.

A Lock consists of a Chamber with Watertight Gates at each end and some Valves

Of course, iron ore is heavy.  As is a lot of the bulk freight shipping on the Great Lakes.  Making those portages around rapids and falls difficult and costly.  They needed to find a better way.  And they have.  Which is why Great Lakes freighters can travel from the western end of Lake Superior to the Saint Lawrence River.  And ocean-going freighters can enter the Saint Lawrence River and travel to the western end of Lake Superior.  Without a single portage.  Thanks to canals.  And locks.

A canal provides a passage around rapids or falls.  And locks in the canal can raise or lower a ship to the water level at either side of the rapids or falls.  Getting around the rapids between Montreal and Lake Ontario and in the St. Marys River didn’t require long canals.  Just enough to provide a passage around the rapids.  The Niagara River posed a bigger problem.  For there were both rapids.  And Niagara Falls.  As well as a great change in water levels.  The level in Lake Erie is 326.5 feet above the level in Lake Ontario.  As the typical lock doesn’t raise and lower water 326.5 feet one lock just wasn’t a solution.  So they used 8 (7 for raising and lowering ships and the 8th as a control lock).   And dug a canal across the Niagara peninsula.   The Welland Canal.  From Port Weller on Lake Ontario to Port Colborne on Lake Erie.  Interconnected by 26 miles of canal.  Allowing fully loaded bulk freighters to travel between Lakes Erie and Ontario.  And ocean-going freighters to travel from the Atlantic ocean (and the world beyond) to the western end of Lake Superior.

So how does a lock work?  Are there massive pumps to pump in water to raise a ship?  No.  There are no pumps.  Just a couple of valves.  A lock consists of a chamber with watertight gates at each end.  The gates swing open towards the upstream side.  When they close they form an 18-degree angle that points upstream.  So when the water level is higher on the upstream side the force of the water presses the gates closed and makes a watertight seal.  When the water level is equal on both sides of the gate they can easily open the gates.  When a ship enters a lock both gates seal.  If they are lowering a ship they open valves between the chamber and the canal on the downstream side.  The high water level inside the chamber drains until the water levels equalize.  If they are raising a ship they open valves between the chamber and the canal on the upstream side.  Water from the canal enters the chamber until the water levels equalize.  Then the appropriate gate opens and the ship goes on its way.  A very simple and low-tech process.  Allowing ships with deep drafts to travel the oceans.  Rivers.  And inland lakes.  Thanks to navigational aids.  Canals.  And locks.

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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.

www.PITHOCRATES.com

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