4/2/14 Report - How East Winds Work Compared to Northeasters, The First British Sea Dog & A Civil War Prison Camp

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Yesterday  I showed how a Nor'easter affects a beach.  Today I'll show how that differs from a situation where the waves are hitting more from the East rather than the Northeast.  There are some very important differences.

If you didn't read yesterday's post, I'd recommend doing that before reading this one.

I'll start with the same photo that I used yesterday when I showed how a Nor'easter works.  Since this beach already has a long cut, we'll assume that cut was created earlier but now the wind has switched around and is coming from the East, as shown by the long black arrow.

Notice in the picture the wave orientation and direction of the Nor'easter, as shown at the top right of the picture.  That could be the situation that existed when the cut was created.

Below that is shown how the wave fronts would be more parallel to the beach and cut after the wind has changed and is coming from the East.  The straight black line shows how a wave would be oriented, and the long black arrow shows its direction as it hits the beach.

Assume that a single wave, indicated by the long black arrow, comes up the beach and hits the bottom of the cut.  It loses speed and stops and reverses direction, with the water then returning back down the slope.

With a Nor'easter, the water hits from the north, moves south along the beach, and then arcs down and back into the water.  

When the waves are hitting directly at the beach, though, the water goes up the slope and then retreats straight back down the slope.  But what happens then?  Another wave arrives to hit the retreating water from the first wave at some point.  That creates a dead area where most materials that were being moved by the water will be dropped.

The short black arrow shows water from the first wave retreating, and the red arrow shows the second wave coming in.  The yellow star between the black and red arrow is where the incoming wave hit the retreating wave.  That is the dead zone where the flow from both waves halts and where material is dropped.

Of course this happens with every wave.

The yellow star at the base of the cliff shows where the momentum of the first wave stopped before it began to retreat down the slope.

This is very different from what happens during a Nor'easter in which there is a nearly constant flow along the beach front as the water approaches from the Northeast, arcs up the beach and then back down to the South and back into the water.  With a Nor'easter, instead of each wave clashing into the previous wave as it returns down the slope, there is a much more uninterrupted flow which keeps its momentum going and therefore carries more material.

Remember the trigger points that I talked about back probably a couple of weeks ago.  Those are very important and you probably won't learn about them anywhere else.

It takes a certain amount of water flow to pick up and move different objects.  It takes more flow to pick up some objects and some types of objects are dropped more quickly than others.  It will take less flow to pick up and move sand, for example, than rocks.  It will also take more flow to keep rocks moving (unless they are round).  And the sand will not drop out as quickly as the rocks.

The point is that different types of objects will be picked up and dropped at different places depending up on the flow of water and the characteristics of the objects.  That is an important fact.

In the above picture I pointed out two places where objects will be dropped out (yellow stars).  Very movable objects such as sand or small shells that are carried up to the cliff will drop out there, and many of the objects  that are being brought back down the cliff by the retreating water will be dropped where the retreating water clashes with the next incoming wave as the flow comes to a quick halt. This is how a coin line can be created.

The location on the slope where the incoming wave hits the retreating wave will change as the waves change size and as the tides change.  If the swells and waves do not change, the clash point will be higher on the beach at high tide and lower at low tide. 

This illustration assumes that the water is not hitting the cliff with force, but is stopping near the base of the cliff.  In that case, the movement of water between the top and bottom star is relatively slow and light material, such as sand, will be dropped there.

The situation changes a little if the waves are hitting the cliff with force.  Then the cliff face will fall and more sand and other material will be moved by the retreating water until it is dropped, very much of it when it hits the next incoming wave.

If the tide is high and the waves high, so that the water goes up over the cliff, the cliff will be flattened out in a hurry, and a sloped mushy beach-front created.

I think you can now see that there is a big contrast between what happens during a Nor'easter and an Easter.  Of course I've left out a number of factors to keep it simple, but the main thing is that you have a much less interrupted and therefore more forceful flow along the beach with a Nor'easter. 

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The first of the British Sea Dogs was John Hawkins.  After learning from the Portuguese that the Spaniards in Hispaniola would buy as many slaves as they could get, in 1562 Hawkins sailed to Sierra Leone where he bought and captured three hundred slaves to take to the New World.  That was his first trip, and it was profitable as he received sugar, ginger, hides and pearls.

He made a second trip to the New World in 1564,   The second trip was a little more problematic, but he made trades and took time to learn all he could about the Caribbean and Spanish colonies.

On his third trip, in 1566, he was injured in Africa and then when arriving on the Spanish Main in South America, he found that the Spanish were under instructions to not trade with the English.  Nonetheless he managed to make the trades before having his ships damaged by a hurricane.  Then the Spaniards would not allow him to get provisions and refit and he was attacked, leaving only two of his five ships to return to England.  Most of his men were captured by the Spaniards, but he and Francis Drake (who sailed with Hawkins) both escaped.  Drake, in revenge, became a privateer.

That story is told in the West Indian History book that I referenced the other day as well as many other places.

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Here is a link to a good article about a dig about the Civil War prison camp,  Asylum.

http://wfae.org/post/archaeologists-race-against-clock-unearth-civil-wars-camp-asylum

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On the Treasure Coast the tides aren't quite as big today as yesterday, but still bigger than usual.

The surf is around three feet, and it will be about that for a few days.

Beach conditions remain poor for finding old things, but you can still find modern items.


Happy hunting,
TreasureGuide@comcast.net

4/1/14 Report. How a Nor'easter Works, What Happened at Riverbend Park & Seminole War Battle Site

Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Why do people always talk about Nor'easters?  How are they different?  And why are they associated with treasure finds?  Those are a couple of questions I'll begin to answer today.

Here is a picture of a Treasure Coast beach that has a cut running for a hundred yards or more.  It is not a picture of the beach today but was taken some time ago.

First notice the two straight black lines.  The straight black lines show the line of wave fronts as they come up onto the beach.  They are hitting at about a 45 degree angle in this case.

I always talk about the angle that the wind and waves hit the beach.  That is very important and has a lot to do with what will happen to the sand on the beach front.

The picture was taken near low tide when the water was not hitting the cuts.  The cuts were made earlier during the previous high tide.

The small arc (C) in the picture shows how the water of one wave would come up onto the beach and go back down again.  It comes up onto the beach at about a 45 degree angle, moves south and then back into the ocean.

The larger arc (B) would be when the tide was higher or the waves were higher.  The water would come up, cut along the face of the cut and remove sand and possibly other objects back down the slope and into the water.

Typically, one wave will hit the face of the cut, and if it hits with force on the face of the cut, it will knock a slab of sand lose, which will get undercut and/or washed away by the next waves.

One very important thing about a northeaster is that the waves maintain much of their speed as they go up onto the beach at an angle and then back down the slope and into the water.

If you stand and watch when the water is hitting the face of the cut, you will see the water taking sand from the face of the cut and washing it down the slope and back towards the water.

Also if there is a lot of water coming up the slope, if you are digging a target and don't get it safely in your scoop, it will be moved with the water.  So if you know the path of the water you'll usually be able to find the lost target again, usually to the south and down the slope a yard of so, depending upon the density and shape of the target.  A piece of foil will wash away quickly and perhaps not be found again.

When the tide is up and the waves are up and hitting the beach at an angle like this, there is a continual flow of waves from North to South along the beach front in front of the cut.  This North to South almost river-like movement of fast water along the beach front is what makes a Nor'easter different.

Some time soon I'll show how things work very differently when the waves are not hitting at much of an angle.

Remember, it takes more than big waves and high tides to create erosion on a natural beach.

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It seems that history is never as simple as its made out.  There is always a perspective or bias of some sort.  I don't think that can be entirely avoided.

I once picked up a history book in a thrift store that had been used in a school in the West Indies.  The title is West Indian History.  It starts with Columbus and goes through the early days of colonialization, slavery, the Sea Dogs, buccaneers, etc. etc.  Pretty good reading, but it treats the British kindly, which is not really surprising considering the author and publisher.

One student had written 1955 in the book, which was first printed in 1936, so I guess it was still in use in the fifties.  

Anyhow, yesterday I mentioned that there was slavery and brutality in the New World long before the white men arrived.  As this school book points out, there was also slavery in Africa before Europeans got involved.  And the Spanish colonizers had large numbers of slave imported to the New World before other European groups got involved, other than the Portuguese who often purchased slaves from African tribes who enslaved members of other African tribes, and then exported them to the New World.

It would be easy to get the idea from what you hear today that white plantation owners in the South were responsible for slavery in the New World, but slavery was in both the New World and Africa before the white man became involved, and the Spanish colonial system in the New World made use of both native and imported slaves long before the British had significant settlements in the New World and long before the US was born.

You'll find a good description of some of that in the articles linked to the bibliography that I gave you a few days ago.


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Do you know what happened at the site of Riverbend Park just south of Indiantown Road?

On January 24th 1838 Major General Thomas S. Jesup, accompanied by fifteen hundred troops, met three hundred Seminoles on the banks of the Loxahatchee River in the last standing battle of the Second Seminole War. During the battle General Jesup lead a charge to the river and was wounded. The Tennessee Volunteers, lead by Major William Lauderdale, took most of the casualties. The Battle ended when Col. William Harney and his Dragoons crossed the river and outflanked the Seminoles. Outnumbered, the Seminoles fled into the swamps. Seven soldiers were killed and thirty one wounded, including the General.

After the Battle of the Loxahatchee, General Jesup petitioned Washington to allow the Seminoles to remain in the Everglades and end the war. Washington denied Jesup’s request, whereby six hundred Seminoles were captured under a white flag of truce at Fort Jupiter.

Here is the Parks and Recreation web site link telling about that.

http://www.pbcgov.com/parks/loxahatcheeriverbattlefield/jesupsbattle.htm

That was the site of one very historic battle during the Seminole war.  And despite the pictures we often see, the Seminole forces were not all Native Americans.  A good number were black.


On the Treasure Coast today the high tide will be unusally high and the low tide very low.  The surf will be about two feet.   That means it will be easy to hunt down the slope near the water line at low tide.

Happy hunting,
TreasureGuide@comcast.net