“THE MONUMENTAL FOLLY OF SANDSTONE” EARTHCACHE EarthCache
“THE MONUMENTAL FOLLY OF SANDSTONE” EARTHCACHE
-
Difficulty:
-
-
Terrain:
-
Size: 
(other)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
The City of Liverpool is built on New Red Sandstone and this Earthcache describes how this was formed and an amazing 'job-creation' scheme that led to miles of tunnels being dug under the city over 150 years ago.
GEOLOGY
Sedimentary rocks are derived from pre-existing rocks which have been broken down by frost, rain, wind, ice, river or sea action. The material thus provided is in most cases moved from its place of origin and deposited elsewhere, usually in layers deposited one on top of another. They can be classified on the basis of whether they were mechanically, chemically or organically formed. The first will have been transported into their new position by mechanical means (wind, water or glacier-ice), the second will have been carried in solution and later precipitated out, while the last are formed by the accumulation of the dead remains of once-living plants and animals. They can also be grouped according to the nature of their chief constituent and sandstones fall into the ‘arenaceous’ group as the grains are quartz with a size typical of that of sand (0.1 to 1.0 mm diameter).
Liverpool is largely built on New Red Sandstone – a rock that was laid down over 90 million years during the Permian & Triassic periods. The red colour is due to the presence of red iron oxide, which is found as a thin film surrounding each grain. This indicates the layers were deposited under desert conditions. The ‘classic’ type of this rock is known as “Penrith Sandstone” which shows overlapping dune-bedding and often almost perfectly spherical particles – evidence of the long-continued rolling to which wind-blown grains are subjected. Deposits vary greatly in thickness but a boring at nearby Formby proved the sandstone layers in Lancashire and Merseyside can be at least 2,360 feet thick. The grains are thought to have been eroded from the uplands of “St George’s Land” which 280 million years ago occupied what is presently Central Wales and Midland & Southern England. Then it was part of the vast Pangaea Supercontinent situated just north of the Equator!
Because the small rounded grains of quartz are only cemented together by a scanty bond of silica, iron oxide or some other material, ‘sandstones’ tend to be soft rocks, ideal for cutting in to blocks of building stone. Often it is quarried ‘open-cast’ from the surface but sometimes it is quarried underground leaving large caves or tunnels. Many of the buildings and walls in Liverpool are built with blocks of this material.
THE FOLLY
A ‘folly’ is a construction built for no real purpose other than to impress strangers or to gratify its owner, usually a rich person. At the co-ordinates you are near one of the entrances to the most amazing subterranean labyrinths in England and possibly “the largest underground folly in the world”, for under the streets of Liverpool run miles of underground passages, chambers and caverns hacked out of solid sandstone between 1806 and 1840. They are now known as Williamson’s Tunnels after their creator, the philanthropist Joseph Williamson (1769-1840). He became rich as a tobacco merchant and created an early form of ‘Welfare state’ for men, unemployed after returning from the Napoleonic Wars. He gave them money provided they worked and cut his tunnels under the city. Nobody today really knows what their purpose was – it does not appear to have been a simple quarry for there are highly crafted arches lined with intricate brickwork, buttresses and even spiral staircases cut out of the sandstone. A ‘Triple Decker’ tunnel has been recently been found, more than large enough to garage several double-decker buses! Much of system of tunnels was filled with rubble, dumped by Victorian fly-tippers, and they lay untouched & forgotten for over 150 years. Volunteers are now seeking to rescue and renovate this mysterious underground world built by the “Mole of Edge Hill” and have so far found 3 entrances. The one at the co-ordinates is the site of the Williamson’s Tunnels Heritage Centre and there are others in Mason Street and Paddington, opposite ‘The Bear’s Paw’ at N 53. 24.370 W 002 57.434 You can find out more about them at www.williamsontunnels.com
Alas the original task to log the earthcache became unavailable due to reorganisation of the entrance area so the earthcache became archived for a period but new tasks were devised during a visit to the CO's home town in April 2012.
Please e mail the following information, making sure the "I want to send my email address along with this message" box is ticked for faster reply by smart phone:-
1) What dates does the black sign on the wall give for the "Pioneer of Tunnels"?
2) In the corner of the yard by the visitor parking area is a small raised bed with a Himalayan cedar (Cedrus deodora).
Some of the blocks around this are sandstone but there are at least two other types of rock visible. Name 2 of these. There are no notices around locally to help you but they are fairly easy rock types.
3) At the street corner near the entrance to the FOWT site next to a lampost is a large cuboid sandstone block. Look at it closely and tell me whether it is coarse or fine grained. Does it look as though it could have come from the tunnels?
4) Measure it's dimensions. From these you can estimate its volume in cm cubed and its weight, knowing that sandstone has an average density of 2.5g/cm3
Additional Hints
(Decrypt)
Guvax nobhg orpbzvat n Sevraq bs Jvyyvnzfba'f Ghaaryf naq fgnl va gbhpu jvgu qrirybczragf.
Treasures
You'll collect a digital Treasure from one of these collections when you find and log this geocache:
Loading Treasures