Small cistern - Maidenstone Hill

A small bottle-shaped cistern recently turned up at one of the older houses in Maidenstone Hill; smooth rendered inside, about 1m x 2m with a current depth of about 1.5m to the spoil heap. Age unknown (late Georgian?), probably with altered uses over the years - ie cistern then cess pit then rubbish pit. Extremely difficult to photograph inside without an ultra-wide-angle lens. At one end a 2 inch lead pipe leads in and dives down vertically into the spoil heap, destination unknown; at the other a 5 inch earthenware pipe enters, possibly for sewage.

I'm afraid it's not exactly a huge length of passageway or a vast cavern, but the lead pipe may lead back to something altogether much bigger and more exciting - like a conduit.

Two Blackheath Ice Houses

Ice Houses are like buses here at SubG; you wait ages then two come along together. The two here are both on the West side of the heath, and only about 6 or 7 minutes walking time apart. It's quite likely they were constructed within a few years of each other, possibly even by the same builder. Both were almost certainly the typical half-buried egg shape with a double brick skin covered with a mound of earth; a brick drain at the base would have removed meltwater.

One was in the garden of a substantial 18th century villa on Dartmouth Row, close to Dartmouth House, and alas has now been destroyed and heavily built over. The other was located on a three acre plot of land leased by Lord Cardigan in 1758 from The Legge family, the Earl of Dartmouth and Viscount Lewisham. Its circular foundations were discovered many years ago in a garden on Eliot Vale and promptly misdiagnosed as a signalling beacon - with Tudor brickwork to boot - by someone clearly unversed in the principles of archaeology. Traces of the Eliot Vale ice house may still exist; we are in discussion with the relevant landowners to investigate the location.

You might also be interested in this post about the Brooklands Ice House in Blackheath, another 18th century example.

Watch out for idiosyncratic compass orientation in these plans...

↑ North is bottom left; click for larger version (496k 1000 x 674)

↑ North is at the bottom; click for larger version (572k 962 x 704)

Conduit engineering

An accurate vintage cross-section through part of Queen Elizabeth's Conduit (near the old drinking fountain below Queen Elizabeth's Oak) - the open brickwork to allow water to percolate into the passage is clearly shown. The lead-lined gutter collected the water and passed it through a lead strainer to a settlement tank, from where it was piped down to the Royal Hospital.

↑ Click for a larger version (1.27MB 1500 x 1391) Image: London Borough of Greenwich Heritage Centre

Staircase into Hyde Vale Conduit - photo discovery

Remarkable historic photos have come to light showing the archway which opened into the staircase of the Hyde Vale Conduit halfway along its length. The date is probably around 1900; a newly-discovered contemporary photographic view down the valley also shows the archway, with its light-toned stone plinth being easy to see. We had been hoping to unearth something like this for 25 years, and are delighted to finally publish these fascinating pictures for the first time ever.

Click here to see the main post about the Hyde Vale Conduit.


↑ Click for a larger version (1.14MB 1500 x 1084)


↑ Click for a larger version (1.45MB 1500 x 1458)


↑ Click for a larger version (1.19MB 2000 x 1461)

Photos above by courtesy of London Borough of Greenwich Heritage Centre

Dartmouth Row - 18th century brick drain

A vintage subterranean photo probably taken during the 1940s, showing an 18th century brick drain found in the garden of a house in Dartmouth Row. At the same property we examined a well with a short length of small passageway attached, but were unable to find the drain in the photo. The house number has been censored to protect the occupants from excessive public interest.

↑ Click for larger version (490k 800 x 857)

↑ Click for larger version (417k 800 x 880)

Both photos Copyright: Trustees of the late Alan Roger Martin.

Admiralty Western Reservoir - revealed

At the beginning of World War II the Admiralty Western Reservoir (the large subterranean structure a few metres uphill from the Standard Reservoir building) was opened for use as an air raid shelter. Here is a unique photo showing the works in progress:

Copyright: Trustees of the late Alan Roger Martin. Click for a large version (2.04MB 1500 x 1600)

Sayes Court mine, Deptford

On John Evelyn's 1653 plan of Sayes Court in Deptford (Copyright © The British Library Board), there is a sand or gravel pit shown at the bottom right corner - with the entrance to a mine gallery clearly shown. To the untrained eye it may not look very clear, but once you understand the artistic conventions of the 17th century, it becomes obvious. Compare the method of showing the entrance with that used in the painting/plan (inset in second image) of Maze Hill mine - the technique is identical. Presumably it was a sand mine, as the alluvium which occurs in this area of the Thames valley is of little commercial value.

Our Correspondent "K" makes interesting points about the pit - that it already existed when Evelyn made the drawing, so predating 1653; also Evelyn's comment on the pit area: "an extravagant [=overgrown?^k] place mangled by digging gravell"

↑ Evelyn's plan of Sayes Court 1653 (Click for a large version 435k 1600 x 1387) - look in the bottom right corner, and you will see this:

↑ A closer view - inset shows the contemporary depiction of entrances at Maze Hill mine. Click for a slightly larger version 160k 494 x 464

The main objection to the mine existing is that today there appears to be insufficient vertical space between the high water mark of the Thames and the land surface to dig a mine gallery. However, that difficulty can be overcome by looking at the date of the plan - 1653 - during the LIA (Little Ice Age) when the average sea level was at least 25cm lower than it is today.

The Wikipedia article defines the LIA very well:

The Little Ice Age (LIA) was a period of cooling that occurred after a warmer era known as the Medieval Warm Period. While not a true ice age, the term was introduced into scientific literature by François E. Matthes in 1939. It is conventionally defined as a period extending from the 16th to the 19th centuries, though climatologists and historians working with local records no longer expect to agree on either the start or end dates of this period, which varied according to local conditions. It is generally agreed that there were three minima, beginning about 1650, about 1770, and 1850, each separated by intervals of slight warming.

↑ The fall in global sea level during the LIA is very clear.

Note that the plan was drawn in 1653 - coinciding exactly with the first Minima of the LIA, when sea levels would have been at their lowest.

If any of the gallery/mine still exists, it is now probably partially flooded and in a highly dangerous condition.

↑ The pit was on the south side of Leeway, which partially follows "the old watring pond" alongside the pit^k (click for a larger version 356k 659 x 610). The area shown in the bird's-eye view is still much the same now. It's the far corner of Convoys Wharf.<sup>k

k</sup> Words of Correspondent K