The Hidden Landscape

Focalplane

Western Thunderer
Another journey down memory lane. One of my classmates at university came from “Elt-um“. He made his 3rd year project a study of sharks teeth from the yellow coloured “Wroot-um” beds where the brick pits are. He gained a 1st class honours partly as a result. Funny thing was he went to a “red brick” university.
 

Tim Watson

Western Thunderer
I would strongly recommend Farrow & Ball colours in sample pots for painting buildings. The paint is very good quality and they have useful colours: ‘London Clay’, ‘London Stone’ etc. However, I generally avoid pubs that have been ‘Farrow & Balled’ as there value to quality ratio is usually poor.

Tim
 

Pencarrow

Western Thunderer
When researching the North Cornwall Railway for our Treneglos layout one thing that intrigued me was the different materials used for the station buildings long the line.

Generally local stone was used unless this was unsuitable and then brick was used instead. Interesting to see how the local geology is reflected in the buildings in such a relatively short distance.
 

Focalplane

Western Thunderer
The discussion above mentions the slope of an embankment which should be directly related to the stability of the strata that was excavated. Staying in the southeast of England, the Chalk is a soft rock (hit it with a hammer and most of the time you will get a thud rather than a ringing sound). Yet it will stand up with remarkable stability due to the interlocking nature of the component micro fossils. The White Cliffs of Dover are still there after 10,000 years.

When the M40 was excavated through the Chilterns many were surprised to see the Chalk left as a near vertical cliff. Although some degradation has taken place, the cutting is still there today. When I used to take the train from Southampton to London in the 1960s I remember the chalk cliffs at Micheldever Station where the LSWR had created sidings. They are still there today.

Move to Wales and the cutting at Talerddig had near vertical walls between hard rock. Still standing!

The worst case for modellers will be soft clays prone to earth movements. Low angle embankments take up space that we often don't have. Some of these have become news in recent years - the Harbury landslip being an economic disaster for the Chiltern Line. A whole new science has developed around such problems and there is debate as to how best to prevent landslips.

Here is a good link (there are many more images on line):

Harbury Tunnel landslide: an update from Network Rail

Incidentally, the Harbury line was designed under the management of I K Brunel. He also managed the similar cutting at Mickleton Tunnel on the Cotswold Line. Those were early days, though, when "Geotechnics" didn't exist as a university degree course.
 

Allen M

Western Thunderer
The Severn Valley Railway has throughout it's entire life has had landslips and a lot of ongoing work to stop them. Much of the route is sandy and/or other soft material which does not bind very well.
Regards
Allen Morgan
 

simond

Western Thunderer
Paul

“Staying in the southeast of England, the Chalk is a soft rock (hit it with a hammer and most of the time you will get a thud rather than a ringing sound). Yet it will stand up with remarkable stability due to the interlocking nature of the component micro fossils. The White Cliffs of Dover are still there after 10,000 years.”

Well, they’re still ‘ere, but they ain’t the same shape :)


upload_2020-10-23_20-45-14.jpeg

photo from an interesting article at

Folkestone Warren, Kent - landslide case study - British Geological Survey

Atb
Simon
 

Focalplane

Western Thunderer
OK Simon, the instability caused by a sudden rush of North Sea ponded water into the Channel caused a lot of instability 10,000 years ago. One of the aspects we shouldn't forget is that we, as a species, have evolved during a very unstable period after four cycles of Ice Ages. Add our own sense of being in control has just made things worse!

I maintain that the Chalk is stable within itself, the underlying Gault clay is the problem at Folkestone.
 

Yorkshire Dave

Western Thunderer
When the M40 was excavated through the Chilterns many were surprised to see the Chalk left as a near vertical cliff.

Having studied geology myself I wouldn't have be surprised. When living in Aylesbury, and later Luton, I saw a quite a few roads either newly excavated or widened thorugh the Chilterns. Steep sided cuttings abounded. The geology along any given route, I suspect, affects the £ per km - the more stable the geology the less there is to excavate.

Tring Cutting was also cut through the Chilterns. This is my dad's photo (early 60's) taken from the Startops End - Pitsone Green road bridge (looking south) where the cutting flattens out. The steepness of the chalk sides is more noticable from the next bridge south on the road from Bulbourne towards Pitstone/Ivinghoe.

Tring Cutting.jpg
 

Osgood

Western Thunderer
........
I maintain that the Chalk is stable within itself,.........

Yes, but - you never know what's under your feet.

Around the mid 70s, towards the end of the non-articulated shovel epoch (some considerable time after the Cretaceous period ended), the very machine pictured below had just grabbed a bucketload of what was once the beach but now some 15 miles inland from the current sea boundary, 30 ft below ground level and 2o feet above the top of the chalk, when it promptly dropped 15 feet, together with an area of surrounding surface some 30ft across.

The cause was a large solution hole (a cavity or chamber usually formed by groundwater flow dissolving away the chalk, the roof of which had been repeatedly collapsing and working its way upwards over maybe tens of thousands of years until the weight of the loader gave it a kick up the proverbial).


Michigan 125A.jpg
 

Osgood

Western Thunderer
Don't panic - we haven't lost anything else.

Although my car did once partially disappear - but that turned out to be failure of the lid of the septic tank, not a solution hole!
 

LarryG

Western Thunderer
Topography and what lies beneath the soil is fascinating. I remember when the red walls of sandstone at Stockport became visible to motorists after the motorway took over land where the Cheshire Lines Railway once existed.

It is a steep climb out of Stockport to the top of the hill at Gee Cross, then its downhill again through Hyde to Ashton-Under-Lyne. But once again there is the climb to Oldham, downhill to Royton, a climb to summit, then it downhill into Rochdale. Therefore, life for the railway builders in the 18th Century was not easy when railways do not like gradients. Progress arrived in the wrong order!

Had petrol and diesel propelled road vehicles arrived before steam, railway might never have been built in Britain. The construction of inclined trunk roads would have been a far easier proposition with the primitive tools available in the 18th Century than building embankments, cuttings and tunnels for railways.

The history of film stock was the same. Who would have used black & white film had colour film come first!
 

simond

Western Thunderer
Interesting thought, Larry. Electricity was certainly available around the same time as early steam. Our railway maps would have looked quite different had the development of high voltage & high power coincided with the railway boom, as following the contours would have been much less necessary - see the LGV in France, much, much straighter.

Tony, it was the NR strategy report that led me to the RGS Folkestone Warren one.

path
Simon
 

Focalplane

Western Thunderer
Here is an excellent book I can recommend:

Building the first inter-city rail link – The story of the London and Birmingham Railway

Actually, the link is to a video from History West Midlands, but there is a book containing many of the lithographs that feature the building of the London & Birmingham Railway. The vista of the cutting at Tring may be a bit fanciful but otherwise the artwork is magnificent.

Some in the "North" will baulk at the description of the L&BR as being the first inter-city railway but there are two caveats - the first inter-city railway to enter London and the distance in excess of 100 miles were definitely "firsts". Put another way, the Grand Junction Railway (Liverpool to Birmingham) was the least celebrated of the early rail transport links, largely because the directors wanted to keep the opening of that line low key due to the death of their friend, the MP who died at Rainhill. Yet it arrived in Birmingham before the first train ran from London.

I have a copy of the book, the Picturesque Railway, but cannot find it at the moment. It is available from some sources and may need to be tracked down because History WM appear to have sold out.
 
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