Sound Mirrors uncovered at Fan Bay near Dover

I mentioned that, last Saturday, we attended the South East Region Industrial Archaeology Conference [SERIAC], held at Dartford Grammar School. I attend Surrey Industrial History Group talks, which is where I learned of the conference.

SERIAC is an annual one-day conference organized by a group of Societies in the southeast of England who have an interest in industrial history and archaeology.

In the conference programme there was one talk I was keen to listen to. It was on the subject of Sound Mirrors, and in particular the recent uncovering of two lost sound mirrors at Fan Bay near Dover.

Sound Mirrors were built between the two world wars as early warning detectors of approaching enemy aircraft from the sound of their engines. The convex mirrors work by concentrating sound waves of the plane’s engine so it could be heard before it was visible.

There are Sound Mirrors on the coast in Kent and a number in Yorkshire, built to give advance warning of approaching enemy airships. The increase in speed of aircraft and the invention of radar rendered them obsolete.

I’ve seen the sound mirrors at Denge in Dungeness from a distance, and have long wanted to learn more about them and to visit some.

Robert Hall’s lecture, in which he briefly described their history, focussed on the uncovering of two lost sound mirrors at Fan Bay, near Dover. Here are a few photos of his slides.

To learn more about these interesting monuments in our landscape, I recommend these web sites,

Attending the South East Region Industrial Archaeology Conference

Here’s a right oddity. We, that’s my dear wife and myself, attended the South East Region Industrial Archaeology Conference[SERIAC].

SERIAC is an annual one-day conference organized by a group of Societies in the southeast of England who have an interest in industrial history and archaeology. SERIAC 2019 was held yesterday, Saturday 13th April, at Dartford Grammar School, and was hosted by Kent Archaeological Society.

There were seven 45 minute lectures/talks on a variety of topics, some of which I’ll tell you about in the coming days. Why did we attend. Well, I particularly wanted to listen to one talk, and I persuaded my wife to join me as she there was a talk she might find interesting. As with all conferences, not every talk was riveting, and I admit to closing my eyes during one talk. We managed to keep our purchases of books to just a couple, and I’m proud of ourselves for that restraint. On reflection, my wife was stoic, and sat through all the talks.

Conference registration was held in the Mick Jagger room, so I guess Mick Jagger is a past pupil of Dartford Grammar School. Here are a couple of photos of registration and the conference itself.

The 43rd series of Industrial Archaeology Lectures concluded this week

I might have mentioned that I’ve been attending the Surrey Industrial History Group’s 43rd series of Industrial Archaeology Lectures – see HERE and HERE for a couple of reports.

There have been eleven fortnightly lectures, held in the Science Park in Guildford, of which I’ve attended eight. Some of the lectures have been on obscure topics, but all knowledge, as they say, is valuable.

The final lecture in this 43rd series by David Waller, author and former Financial Times journalist was entitled, Iron Men: 19th century Engineer Henry Maudslay and his circle. Drawing from his book Iron Men.

Working for engineering companies in the West Midlands in my early years, I saw my region as one of the main areas of the industrial revolution, along with Manchester, of course. I hadn’t considered London as being part of it, that is until David Waller described the inventions of Henry Maudslay and his factories in London, just off Oxford Street and later at Lambeth.

Maudslay is credited with developing the first industrially practical screw-cutting lathe in 1800, and later with the bench micrometer.

We British love our specialist interest groups

Perhaps I should join the Surrey Industrial History Group, as I seem to be attending all of their 43rd evening lecture series this year. Too lazy to complete the application form, probably.

This week’s lecture was Paper and Making it by Machine by Phil Crockett, Treasurer of the British Association of Paper Historians.

Phil’s lecture examined the progress of mechanisation in papermaking. While the principles of the process of making paper have not changed, Phil’s lecture showed how much mechanisation had changed the way paper is made.  Any of the YouTube videos show modern paper making.

While I enjoyed the lecture, what struck me was that there was an organisation purely dedicated to the history of papermaking. Is it something in our British character that prompts people to establish such organisations, and others to join them?

Scouts and children collect conkers for munitions in WW1

Here’s a fascinating story about conkers. Before I get to them, I need to give you a short preamble.

At an evening lecture this week of the Surrey Industrial History Group, I listened to a talk by Martin Adams, Emeritus Professor of Microbiology at the University of Surrey, entitled Conkers, Cordite and the Birth of Modern Biotechnology.

Martin Adams only got round to talking about conkers at the end of his talk. He preceded by describing the discovery, history, and making of acetone.

Acetone is a colourless flammable liquid that was required for the making of Cordite, an explosive  propellant used in military shells and rifle cartridges in World War 1.

Prior to WW1, Britain imported acetone, mostly from America. Wartime made imports difficult, and so Britain needed to manufacture it herself. Secret factories were established to make acetone from a distillation process using maize starch. Should you want to know more about this process, then HERE is a useful, and not too technical, start.

Maize starch, again, much imported from America, was needed both to make acetone and for food production. Therefore, in 1917 other sources of raw material for the acetone distillation process were needed. It was discovered that horse chestnuts – conkers – could be a good source.

In 1917 a circular from the Board of Education was sent to schools to mobilise children to collect conkers and deliver them to railway stations for onward shipment to a secret factory in Kings Lynn. Here’s a photo of the letter, taken from Martin Adams talk. Click on image to expand.

The collection of conkers was hugely successful. The means of transferring them to the secret factory was far less successful, such that much of the collected conkers were left to rot at railway stations through complications with transport arrangements.

It was also discovered shortly after the Kings Lynn factory began distilling the conkers for acetone that it was too troublesome a process and resulted in a lot less acetone that was expected, and also that the quality of the conkers were too variable. The factory ceased using conkers after three months. The need for acetone to make cordite reduced dramatically at the end of WW1, so there the story ends

Here are some sources for this story you might like to read.

Marvelling at the dedication of enthusiasts

Our human response to the dedication of enthusiasts to a subject, no matter how obscure, is to marvel, and admire. Occasionally, this response is ‘wow’, when the dedication is to a subject is way out of normal mainstream enthusiasms. It is a ‘wow’ response that I would like to tell you about.

I’ve mentioned HERE the 43rd series of Industrial Archaeology Lectures by the Surrey Industrial History Group. To date, I’ve attended the first and second lectures in the series, on Brunel, Scott Russell and the Great Eastern, and London Underground’s Edwardian Tile Patterns.

Douglas Rose, London Historian and information designer, gave the lecture on London Underground Edwardian tile patterns. Douglas began collecting details of station Edwardian tile patterns in the early 1980’s. In the mid 1980’s London Underground began a programme of station modernisation to keep pace with the increase in passenger numbers. New ticket barriers were added as were structural changes, in some cases, to fit escalators. These changes involved the removal of the old tiles, to be replaced by new tiles and new tile pattern designs. Douglas couldn’t have found a better time to begin his mammoth project.

To faithfully record the Edwardian tile patterns, running to around 300 feet of station platforms, Douglas evolved a way of capturing the patterns onto a survey grid. The tile patterns varied by station, and within a station the pattern was affected by passageways and equipment boxes. See below [click on image to expand] the survey form used by Douglas and his team of fellow enthusiast recorders.

Listening to Douglas talk about having often to remove grime, paint and posters to uncover the tile patterns, and all at night when the Underground power was switched off, increased my admiration of his efforts. One might even say his, and his team’s devotion, is heroic.

Douglas has been generous in allowing me to post some of his images, see below [click on image to expand]. These are Douglas’ words about the images.

The images are all from Regents Park. The top photograph is from inside an equipment room in the shield chamber on the northbound platform at the left-hand end. This gives a flavour of the difficulty of getting to much of the original tiling, being in a locked small room and with equipment fixed in the way. The second photo is of a pattern panel showing obscuring posters. The bottom photo is of a name panel and is of the earlier and heavier style used only on the Bakerloo stations. The realisation is of panels 1, 2 and 3 at the left-hand end of the northbound, showing a small section of the eventual realisation – there were 16 panels along the full length of the 292 ft platform (which was extended to about 350 ft much later on to take longer trains.

The project involved 2,000,000 tiles on over 90 platforms and after 26 years; truly a marvel at the dedication.

Early notice of lecture series on industrial archaeology

Surrey Industrial History Group hosts an autumn and winter lecture series at Guildford that sounds appealing to anyone interested in the history of the world of transport, and industrial infrastructure. The complete programme brochure, part of which is shown below, can be viewed HERE.