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Thursday 22 June 2017

Fownhope Local History Group in Presteigne 22 June 2017

The Judges' Lodging 

Presteigne is an odd place to get to - comparing notes in the car park on arrival, I'm not sure any of us drove the same route from Fownhope! Still it makes for varied journeys and opportunities for going a different way home. 
A short walk brought us first to the corner by Radnor House with its "Arts & Crafts" painted plasterwork, and then to Broad Street - our goal was halfway down on the right and I was intrigued to see a "blue plaque" on the Red House, part way down, showing that Admiral Puget, after whom Puget's Sound was named, lived here at the beginning of the 19th century.
Radnor House facade was given a makeover in the 1890s, in Arts & Crafts style. There's likely to be an older facade behind

Detail of the decoration on Radnor House

Blue plaque on a Red House

The Red House in Broad Street, Presteigne
A shame about the cars, but this street is nonetheless lined with attractive buildings.
Looking up Broad Street, with the Judges' Lodging, Shire Hall and Red House on the left hand sice

Looking down Broad Street
Meeting up outside the Judges' Lodging - Beryl, Jan, Harriet and Chris

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When we had all arrived we were given an introductory talk - his first attempt at this it turned out - before being let loose with guide books and walkmans to explore the ground and first floors and the basement of the building
An introductory chat - Beryl, Chris, Pam and Harriet
The assizes used to be held in Rhayader but that was "Indian country" backalong, and after a judge was murdered in the 1530s, the court was shifted to Presteigne in 1542 (which was presumably closer to civilisation ;) )

Stairs to the first floor with impressive matching carpet and wallpaper

The table set for dinner
Heading down into the basement we found what was, to me, one of the most fascinating parts of the house, the huge kitchen, complete with enormous dresser, range, massive table etc. All lit by oil lamps and gas flares (predated mantles) so a bit of a paraffin niff, but very atmospheric
The kitchen - I particularly liked seeing the meat hastener complete with bottle jack, on the left as I'd been fascinated by an illustration of this in my Uncle Jack's cookery book. He was a chef at the Royal Clarence in Exeter some 80 or so years ago, and his "Bible" was not Mrs Beeton but a 1909 edition of Hermann Senn's "New Century Cookery Book" . 

Pinnies hung in a neat row

A dresser took up the whole of one wall

This cooking range was previoiusly hidden behind a more modern stove.

The kitchen
Staircase up from the holding cells
 From the kitchen we found our way past holding cells and a privy, onto some stairs which led us up into the dock in the court room! A clever recording of a trial, with microphones playing the different voices placed in appropriate positions about the room.
Three enormous windows at either end light the court room
Some of the glass in the court room windows is beautifully rippled
Read about it here 

We went our separate ways for lunch - there were various places in the town but, as we had Libby the dog with us we found a nice quiet lane where we could park and she could potter around while we ate our rolls
Belinda the Romahome in a pleasant dead-end lane near Stapleton - just right for Libby!

Stapleton Castle

After lunch we met up again, just back across the River Lugg into England, at Stapleton for a guided tour of the privately owned castle by the owner.

None of your manicured English Heritage sites here - a field with sheep, nettles and thistles!
The castle is on a prominent hill above the hamlet of Stapleton but unfortunately the geology is a bit of a mystery as this "sheet" hasn't been mapped at a sufficiently large scale. The best that the BGS can come up with is that it is from the Pridoli Epoch at the end of the Silurian - a mix of mudstone, siltstone and sandstone. Apparently there's a quarry on the far side of the hill, so need to have a look sometime!
Our guide led us up the hill, pausing to explain features as we climbed: the castle itself no longer exists, although the motte and bailey are visible. The castle became superfluous after Glendwr's rebellion at the beginning of the 15th century and was slighted in 1645 during the Civil War, the stone being sold off or used to do some rebuilding or adaptation as it was still lived in.
On our way up the hill. You can just see the houses in the hamlet peeping through the trees.
We could see where the towers of the gateway had been, and also the track of the roadway up to the castle entrance
Heading around to the far side of the ruins we found there was a deep ditch separating steep banks, although these would have been much steeper and deeper when they were there for active defence of the castle.
Wildlife diversion - a Red Admiral. One of the group also checked out a sheet of corrugated iron for grass snakes, but there were none in residence!

The steep side of the motte on the left and the remnants of a ditch below it
:Looking up to the ruins, the scree on the side of the motte is from a recent wall collapse
A drawing of the castle before it became so ruinous

Our guide explained the relationship between the visible ruins, and the old drawing

A remnant of the NE corner - windows were filled in, not to escape Window Tax but to make the room more suitable for use as a larder!
Closer view of the filled in windows. The stonework is a mix of well cemented, hard sandstone for the quoins and less competent sandy siltstone for the bulk of the walls. Window arches are of brick

The rooms at the SE end originally had large windows but these were later narrowed, perhaps to make them more structurally sound. Some of the stonework is in a very precarious state!


An existing plan shows the house had an H-shaped floor plan
I particularly liked this chimney: the first floor level shows clearly, and also the way that the two fireplaces (one on each floor) were lined with brick
A geological aside: the Lugg valley here is pancake flat, explained by a map we found in the Judeges' Lodging (below)
This map shows the lake which would have occupied the Lugg valley at the end of the last glacial: lake sediments have built up to produce a flat lake bed.
We returned via the mill pond - originally fish ponds, then an ornamental pool, then a mill pond and now the silt dredged from it has helped to make the lovely garden more fertile!
The header pond for the mill

Tea and cake before a wander around the garden, and a raid on the plant stall!
Many thanks to the organisers, and to our guides at both venues!

Sunday 11 June 2017

Carbonate ramp at Three Cliffs Bay

OUGS Severnside trip Sunday 11 June 2017

Carboniferous Carbonate ramp at Three Cliffs Bay, Gower

Gower is a good way from Hereford so we went down on Saturday and, after lunch with friends, headed onto the campsite. Saturday weather wasn't good. Fingers crossed for Sunday! The one consolation was that the shower block at the campsite was amazing - individual shower rooms with loo, basin and underfloor heating, and loads of hooks to hang your stuff on! A ridge of land on the seaward side gives a bit of shelter from the strong winds and a wander over this found it is made of resistant Devonian quartz conglomerate.
We headed up the lane into Penmaen in the morning and met up with the rest of the OUGS group in the car park there where our leader, Paul, told us something of what we were going to see before we headed down another lane towards the beach.
Professor Paul Wright making some preliminary explanations, Jan AJ taking it all in, and Andy Mitchell writing it all down for the newsletter report!
We stopped off on the way for a bit of archaeology, the dolmen on Penmaen Burrows: rather ruinous but enough of it can be seen to show that it too is made of the quartz conglomerate which forms the ridge running WNW - ESE from Reynoldstown to Penmaen.
The dolmen on Penmaen Burrows with Libby for scale

Mainly quartz conglomerate, but with occasional rogue clasts like this red one
The last half kilometer is down a sandy path over the dunes (easy down, especially as the gorse roots have thoughtfully been cut so's not to trip you up!) but the ascending the loose, deep sand is going to be a treat to look forward to later on.
The path down through the dunes, lots of little blue pimpernels which I'd seen in Spain but didn't remember seeing in the UK








Looking up Pennard Pill, from the foot of the Burrows, towards the ruins of Pennard Castle

Three Cliffs Bay from Penmaen Burrows



So, having got down to the beach, on to the geology!

The aim of the visit to this locality was to study the early Carboniferous ramp succession deposited during a "Greenhouse" interval when 3rd order sea level changes were taking place. We began at the outer ramp, working our way through oolite shoals to lowstand features including palaeokarst and palaeosols.

The first place we stopped was just above the Lower Limestone Shales (which aren't usually exposed here, but the beach was particularly low). The LLS overlie the Old Red Sandstone and they, and all the other strata we saw, dip steeply to the south making it remarkably easy to look at the entire section as we walked down the beach.

Stop 1, Lower Limestone Shales on the right, and Shipway Limestone behind us on the left
The Shipway Limestone is outer ramp facies, deposited at the start of a transgressive sequence tract.
Shipway Limestone on the right (north), looking south along the cliff exposure we investigated.

Paul gave us some excellent impromptu mini-tutorials - this was about the Early Carboniferous palaeogeography, using a map by Ron Blakey
In the Early Carboniferous we were on the southern side of St George's Land, looking across the Rheic Ocean to the rising Variscan mountains which would eventually reach around 4000 m height. When the Lower Limestone Shale was deposited though it was deep water muds and cherts 9they extend under the coalfield all the way to the north crop.
Then, as the sea shallowed, the younger sequence was deposited on top as a carbonate ramp, sloping very gently south, probably with some distal steepening

Cross stratification in the Shipway Limestone, part of Hummocky cross-stratification showing we were above storm wave base but below fair weather wave base in this distal section of the ramp

Shipway Limestone cross stratification and escape burrows

Another mini-tutorial while people investigated the  partially dolomitised Tears Point Limestone and the interfingered, shallower water, beds of oolite.

Not sure why but the oolite (above) seems to have more calcite veins in it than the Tears Point Limestone

Massive limestones were deposited in deeper water intervals, and oolite in shallower shoals when sea level receded., Libby is intrigued by the Milankovitch eccentricity cycle explanation for 120 ka sea level change cycle.
Quaternary raised beach above a faulted section which repeats the Tears Point Limestone

The Gully
At the Gully, there's evidence of a major drop in sea level, rather than the oscillations that had produced interfingered deep water limestone with shallower oolite. On the right is a karst surface (i.e. subaerial): this is "mammillated" - evidence of vegetation where water dripping off trees resulted in differential cement chemistry and weathering (a feature described in the Bahamas as "banana holes" )
In the Gully itself is the Gully Oolite, part of a transgressive sequence as shoals and then a barrier island built landwards over the karst. Paul explained the planar nature of the beds as resulting from cannibalisation of the barrier island as the water deepened and the sediments were reworked and the island moved inland as the sequence retrograded.
The High Tor Limestone on the left includes a basal transgression conglomerate.
A fascinating section, though the very strong winds, accompanied by rain showers, made it less appealing to study at length so we retreated up the beach and found a more sheltered spot for lunch before trudging back up the steep sand dunes to Penmaen!
Lunch back by the Lower Limestone Shale
Thanks to Jan Ashton-Jones for persuading Paul to lead this trip, and also for arranging a follow up lecture later in the year at our November "Day of Lectures".