Email Dialog with a Geologist.

Oct 16 thru 17th, 2002

Hi Mike

Returned to find a "Mike from South Hampton called" note, which, given
the fact that I have no correspondent from "South Hampton" I take to be
you.
I have no explanation for the cannon and its odd pebbles except one you
have probably already thought of. The cannon is salvage.
If it had originally been embedded in a sheltered sand beach that is
only seriously disturbed during powerful storm surges the conditions for
producing highly smoothed pebbles would be met.  Further, the cannon
would have settled in well. In the normal course of events any sand
would be gouged out around it by wave action, the cannon slowly but
surely sinking further into a level of the beach that was pebble not
sand.  Further, pebbles catching in the hollows that you can watch
forming wherever steady wave action laps around an "immovable" object
would anchor it ever more firmly. In a sense the cannon would be
protected.
One has to consider, however, that cannon are cast carefully and worked
to a smooth finish.  Under fresh water conditions, assuming that acidity
from decomposing organic material is not a factor, some time would have
to pass before enough alteration of the metal would occur to allow any
pebbles (let alone well polished stones) to adher strongly enough so as
not to be easily removed by further action.  The only exception I can
think of would be pebbles with a high content of iron. On the other
hand, if the cannon was recovered from one wreck only to be buried in
another, the presence of other iron objects and rotting wood would
provide better conditions for deterioration and the accumulation of
debris.
Whoever put the cannon into the hold probably realized that it might be
worth a bit as salvage, but in the meantime could serve another purpose.
On the other hand, what better place to hide something big, found on a
beach, that, perhaps, shouldn't remain in the possession of whoever
stowed it away?  It appears to be in rather good condition and I would
hope that some identifying marks still exist.
The rock is interesting. It MIGHT represent unused material which it
was easier to leave as ballast rather than trouble to remove. But,
though I don't know much about ships I can't help wondering, shouldn't
ballast rock be fairly even in size, so that an even distribution of
weight is achieved.  Hugh sharp boulders and meter long cannon seem a
little risky under rough conditions...

Liz


> Michael Sterling wrote:
>
> Liz:
>
> I'll get back to you about the Institute soon.  Right now I want to
> ask you a favor that parallels your work connecting the Light on
> Chantry Island with Inverhuron's Gunn Point and Holmes Bay.
>
> As you  might recall, last year a great discovery was made on the
> beach at Southampton.  Two vessels were found. After some digging by
> professional archeologist' Ken Cassavoy and his colleagues, it was
> found that one was an old barge that might have been used to haul
> stone for the Harbour of Refuge.  The other was an unknown vessel that
> needed more investigation.
>
> This week Ken and crew again did another test dig on the beach moving
> down the keelson to find if the ship was a sailing vessel or powered
> by steam.  Two mast steps were found and it was clearly a sailing
> vessel.  During last years work magnetometer studies had indicated a
> big hit along the keel. True to the instrument data, lots of iron
> spikes were found as expected.   .... but, but, but.....a strange
> object was discovered early this week, but not identified until later
> because of the pressing need to look for the mast steps and other
> details.  Late Wednesday a close look at an object showed it to be a
> small swivel deck cannon!  If you look at www.chantryisland.com you
> will see it on the main page.  This cannon may date from the late 18th
> century according to Ken's sources.
>
> I'd like to ask you a couple of questions about what was found. Here
> they are:
>
>
>   1. Near the main mast step there was lots of ballast as we would
>      expect.  Some of it was rounded beach stone.  If I was going to
>      ballast a ship, I would use rounded beach stone which abounds
>      around here.  Lots of it was found near the keel.  What did
>      surprise me, however, was the abundance of limestone.  I was not
>      surprised at some of the small pieces that were somewhat rounded,
>      but there were too many big pieces that were not what I'd expect
>      as ballast due to their size.  Most ballast for a ship that size
>      would be selected to be easily handled by one or two men, but
>      some weighed upwards of 150-200 lbs and was awkward to handle.
>      In addition it looked to me like stone that was "mined" just like
>      John Brown's.  Having worked with the Inverhuron stone for 4
>      years, I recognized pieces that would not be particularly useful
>      because they were not the right shape or size and would require
>      more cutting.  Some had relatively flat surfaces, however.  I
>      took some smaller samples of the limestone and saved it for you
>      to look at.  We also found some slate which was a mite too thick
>      for roofing, but clearly was of good quality and of course not
>      from nearby.  There were just a few pieces which could be
>      consistent with onetime cargo.  I'd like  you to look at all this
>      too.
>   2. Attached to all the metal found near the keelson were small beach
>      stones as you would expect.  They adhere very strongly to the
>      spikes.  The cannon to my eye was different.  It had the same
>      stone stuck to it, but the stones appeared almost polished which
>      bothered me. They were at the stage where wetting them made them
>      appear highly polished.  That's the stage where a polisher starts
>      to use very fine grit.  I polish stone with grit using 4 or 5
>      grit sizes and finally talcum.  The polish on these stones would
>      be just before the last grit and maybe even ready for the final
>      talcum.   Do you have any way of explaining this due to some
>      natural occurrence?  The beach sand in the area of the wrecks is
>      ordinary and would be my course grit in rocks that I polish.  In
>      my experience it would not be apt to polish them to this point.
>
> In any event, I'd like  you to look at these things.  I can bring the
> stone to you, but not the cannon.  I can probably get one or two
> stones off the cannon for you to look at and some off the other
> spikes.
>
> Mike

Michael Sterling wrote:
>
> Thanks for your response Liz....
>
> I did think of the polishing effect of the wave action.  I'm not sure it's
> all that easy though.  I'll need to take some samples and see if a talcum
> type polish will complete the process.  I know that normal sand action is
> not a good polisher usually, not even as a first grit.  Maybe the water
> action would help.  The wreck is many feet below the surface of the sand and
> has been there for a very long time.

Water action,(direction, normal force, periodicity, etc.), granule size,
as well  constituent minerals of the "sand", and nature of the material
being polished determine the degree of polishing achieved. Just to name
a few factors. Sand, with a sheltered but steady wave action is a must.
The current beach at Southampton doesn't produce really fine beach
pebbles. This is why I suggested that the cannon may in fact be salvage
from another wreck that settled into a bay or beach with the right
conditions.  On the other hand (I've been reading the reports) the beach
at Southampton may have been quite different in the past, before the
extensive work altered currents and wave force. The depth to which it is
buried would suggest that an investigation of strata you are digging
through to uncover the ship might give you some answers.  In the photos
clear stratification reflecting the sequence of infilling is evident.
 
> The cannon is from the late 18th century and it was found at the keelson or
> lowest point on the ship toward the bow.

Could the cannon have rolled there?
This is going back a ways but I seem to recall that cannons often had
marks that identified their origin or certain characteristic subtleties
of design that pointed to country of origin or even manufacturer.
 
> You're right... ballast is usually rounded stone and it's best when one man
> can easily handle one stone.  This size "nests" best.  The larger limestone
> is not good and must have been cargo at one time or a real lazy man's
> ballast.

It does seem a bit sloppy.
 
> Liz, did you find many blast holes down at Gunn Point or Holmes Bay? They
> would be packed with powder to cut the limestone neatly from the rock.

No.  Rock for the kiln was readly available due to wave action or easily
broken up with sledges from larger pieces.  The best way to prepare rock
for building purposes would have been to use feathers and wedges.
Besides which the rock readily fractures into building blocks through
natural processes. Blasting would have been counter-productive.

You might find this of interest.
http://www.rushcounty.org/PostRockMuseum/

Liz

Michael Sterling wrote:
>
> Thanks again Liz....
>
> I don't think the cannon was rolled there ... remember it was not in the
> sand, but inside the ship, probably fallen from the deck mount.  It was
> polished by the sand because the hull soon filled up.

Thought of it as being already in the hold not on deck. OK. I need to
read all the information posted.

Liz