Archive for the History Category

Father Callan and the Induction Coil

Posted in History, Maynooth, The Universe and Stuff with tags , , , , , on July 9, 2019 by telescoper

Historically speaking, Maynooth is more strongly associated with theology than with science but I thought I’d mention here one famous pioneering physicist, who happened also to be a Roman Catholic priest, who spent his working life in these parts.

Father Nicholas Callan (or, more formally, The Reverend Professor Nicholas Joseph Callan) was born in County Louth in 1799 went to the seminary of St Patrick’s College, Maynooth, in 1816 to train as a priest. During his time as a seminarian Callan studied ‘Natural Philosophy’ and became interested in experiments involving electricity. In 1823 Callan was ordained as a priest, and went to Rome in 1826 to obtain his doctorate in Divinity. At the time Italy was a centre for research into electricity and here Callan became familiar with the work of the Italian physicist Alessandro Volta who had developed the world’s first battery. Callan returned to Maynooth where he was made chair of Natural Philosophy, a post he would hold until his death in 1864.

Callan is most famous for inventing the induction coil (in 1836). By connecting two copper wire coils to a battery and electromagnet and then interrupting the current he was able to generate much larger voltages than could be obtained from batteries alone. His 1837 version that used a clock mechanism to interrupt the current 20 times a second is estimated to have produced 60,000 volts – the largest artificially generated charge at that time. It is said that his induction coil could produce sparks 15″ long, which must have been fun to watch.

Callan’s biggest induction coil, unfinished at the time of his death, can be found in the National Science Museum of Ireland (which is in Maynooth). This was one of the largest in the world at the time. The iron core is 109 cm long. The secondary windings are 53 cm in diameter and consist of about 50 km of iron wire insulated with beeswax. They were made in three separate rings separated by air gaps, so wires carrying large voltage differences would not lie adjacent to each other, reducing the risk of the insulation breaking down. At the left end is a vibrating mercury ‘contact breaker’ in the primary circuit, actuated by the magnetic field in the primary, which interrupted the primary current to generate potentials of over 200,000 volts.

Sadly Callan’s work was forgotten for quite a period after his death – experimental electromagnetism was not a priority for St Patrick’s College at this time – for which reason the invention of the induction coil has often been attributed to Heinrich Ruhmkorff who made his first device (independently) about 15 years after Callan. More recently, however, Callan’s achievements have been more widely recognized and in 2000 the Irish government issued a stamp in his honour.

The Callan Building

Nicholas Callan was laid to rest in the College Cemetery at Maynooth in 1864. The Callan Building (above) on the North Campus of the present-day Maynooth University is named in his honour.


Fascist Lookalikes No. 357

Posted in History, Politics with tags , , , , , on July 2, 2019 by telescoper


Have you noticed to remarkable similarity in behaviour between representatives of the Nazi Party elected to the Reichstag in 1930* and representatives of the Brexit Party Money-Laundering Company in the European Parliament in Strasbourg?

I wonder if, by any chance, they might be related?

*In an earlier version of this post I used 1926 (the date given by the stock photo supplier Alamy) but this is incorrecr; the right date is 1930.

On Bumfodder

Posted in Books, History with tags , , on June 21, 2019 by telescoper

It’s not quite the end of the week for me, as I am on duty all day tomorrow for the Summer Open Day at Maynooth University, but I thought I’d end the penultimate working day of this week with a post about a piece I read in the Times Literary Supplement a few weeks ago. I subscribe to this mainly for the crossword, but also because some of the reviews are extremely interesting.

In the May 31st issue of said organ, I came across a review of a book charmingly entitled Bellies, bowels and entrails in the eighteenth century, which is published by Manchester University Press. I’m not planning to buy a copy as it costs £96, but it I was intrigued by the review, which includes such vivid insights as

Stomachs and bellies, hiccups and flatulence dominate the last third of the book…

The thing that really caught my attention however was the issue of toilet paper. As far as I am aware, paper in a form specifically designed for the use of wiping one’s bits clean after defecation wasn’t introduced until the middle of the 19th century, but waste paper was commonly used for that purpose much earlier. In the 18th century it was apparently commonplace to tear pages out of cheap books to use as lavatory tissue, and it appears some people would buy books both to read when on the job and for cleaning up afterwards.

This practice gave rise to the word bumfodder, which the Oxford English Dictionary defines as:

  1. Toilet paper. Also occasionally: a piece of this.

  2. attributive and allusively. Worthless or inferior literature; any written or printed material that is perceived as useless, tedious, or unnecessary.

In case you didn’t know, this is also the origin of the word bumf, which the OED gives as

  1. slang (originally in British public schools). Paper (of any kind). Now rare.

  2. Toilet paper. Now somewhat archaic.

  3. orig. Military slang. Written or printed material that is perceived as useless, tedious, or unnecessary, as bureaucratic paperwork, advertising, etc. Also occasionally: worthless or inferior literature.

I have to admit I’ve used the word `bumf’ in the third sense on a number of occasions without realizing quite how indelicate is its origin.

The first instances of `bumfodder’ quoted in the OED date from the mid-17th Century, which surprises me a little because I was under the impression that paper was an expensive commodity then. By the 18th century, however, it was obviously much cheaper, presumably because of mass production, and so consequently books and newspapers were much less expensive. Waste paper was then used quite frequently not only as toilet paper but also for wrapping groceries and other goods. I should mention, however, that paper was used at toilet tissue in China as far back as the 6th Century AD, so Europe was obviously a bit behind on the matter.

Anyone who has read any 18th Century literature – the humour in which is often rather coarse – will not be surprised by the number of scatalogical jokes about bumfodder going around. Obviously I couldn’t repeat any here.

P.S. Now wash your hands please.

Margaret Skinnider – in her own words

Posted in History with tags , , on June 20, 2019 by telescoper

A few weeks ago, occasioned by a stroll around St Stephen’s Green in Dublin, I put up a post that included the the remarkable story of Margaret Skinnider.

Before the 1916 Easter Rising Margaret Skinnider was a school teacher. During the hostilities she initially acted as a scout and a runner, carrying messages to and from the GPO, but when given the chance she proved herself a crack shot with a rifle and showed conspicuous courage during the heavy fighting in and around St Stephen’s Green. In particular, on 27th April she lead a squad of men in an extremely dangerous mission against a British machine gun position, during which she was hit three times by rifle bullets and very badly wounded.

Anyway, I found this fascinating recording of Margaret Skinnider herself telling the story of her part in the 1916 Easter Rising.

After the War of Independence and the subsequent Civil War were over, Margaret Skinnider returned to her career as a primary school teacher. She died in 1971.

Special 1919 Eclipse Centenary Offer!

Posted in History with tags , on June 13, 2019 by telescoper

A little later than planned, a paper what I wrote for Contemporary Physics to commemorate the centenary of the 1919 Eclipse Expeditions has now appeared online. The print edition will be available in due course.

Here is the abstract:

Unfortunately the paper is behind a paywall, but as a special dispensation I am to offer FIFTY free downloads of the paper to friends, colleagues and random people on the internet.

If you’d like to download a FREE copy of the PDF of the paper A revolution in science: the eclipse expeditions of 1919 then you may do so by clicking this link. How’s that for clickbait?

UPDATE: the free copies have now all gone so I removed the link.

To be honest I’m not sure what stops you sending the PDF to anyone else, but apparently those are the rules…

D-Day 75 Years On

Posted in Art, History with tags , , , , on June 6, 2019 by telescoper

Today is the 75th anniversary D-Day, the start of the Allied landings on the beaches of Normandy. I thought I’d mark the occasion by posting a slightly edited version of a piece I wrote about 9 years ago about this very famous picture:

This remarkable photograph was taken at 8.32am on 6th June 1944 on “Queen Red” beach, a sector in the centre-left of Sword Area, during the early stages of the D-Day invasion. The precise location is near La Brèche, Hermanville-sur-Mer, Normandy. The shutter clicked just as the beach came under heavy artillery and mortar fire from powerful German divisions inland.

Some time ago I came across a discussion of this image in the Observer. As the article describes, it consists of “a series of tableaux that look like quotations from religious art”. The piece goes on

In the foreground and on the right are sappers of 84 Field Company Royal Engineers. Behind them, heavily laden medical orderlies of 8 Field Ambulance Royal Army Medical Corps (some of whom are treating wounded men) prepare to move off the beach. In the background, men of the 1st Battalion, the Suffolk Regiment and No 4 Army Commando swarm ashore from landing craft.

The sapper in the bottom left, looking directly into the camera, is Jimmy Leisk who was born in Shetland. His strained expression gives the impression that he’s trying to escape from the photograph; through his eyes we get a glimpse of the grim reality of armed conflict. His colleague, turning away from the lens, seems to be calling to the men behind, but the image of his head and upper body links with the more distant figures forming a dramatic arc that pulls you into the centre of the picture before veering off to the right. Each element of this image tells its own story, but apart from one person in the foreground, all the faces are all hidden from view. I’m sure these anonymous figures were all just as frightened as the man in the foreground, but their individual identities are lost as they blend into graphic depiction of the monumental scale of the invasion. It’s a truly wonderful work of art, and a brilliant piece of storytelling, at the same level as an Old Master, but this is made all the more remarkable by the fact that the photographer was risking his life to take this picture.

This photograph, which was taken by Sergeant Jim Mapham of the Army Film and Photography Unit, was described by the US Press as “the greatest picture of the war”.

Jim Mapham was one of seven cameramen of the AFPU who went in on D-Day: Sgt Ian Grant, Sgt Christie, Sgt Norman Clague (killed), Sgt Desmond O’Neill (wounded), Sgt Billie Greenhalgh (wounded) and Sgt George Laws. Their work forms an extraordinary record of the invasion and is still widely used by the media – but rarely credited.

Robert Capa, the famous Hungarian photographer, was also on the beaches that morning, pinned down in the waves by enemy fire. But while he clambered on to a landing craft to get his pictures back to London, Sgt Mapham moved inland with the invasion force…

Jim Mapham survived the D-Day campaign and entered Germany with the army to document the fall of the Third Reich and the horrors of the Belsen concentration camp. He died in 1968. Until today I’d never heard of him. His name should be much more widely celebrated. I understand that the complete set of photographs he took on D-Day can be found in the Imperial War Museum‘s photographic archive.

As a final comment let me add that, contrary to popular myth, the landings at the Sword beaches were by no means a pushover. It’s true that the American forces, especially at Omaha beach, suffered heavier casualties on the actual landings – primarily because they failed to get their tanks and heavy artillery pieces ashore. However, the British troops at Sword were the only ones at any of the five landing areas to encounter strong German Panzer divisions on D-Day.

The main assault force at Sword beach was the British 3rd Infantry Division and its primary objective on the day of the invasion was to capture the city of Caen. As it turned out, the fighting was so heavy that they didn’t manage to take Caen until over a month after D-Day.

In fact it is worth remembering that the Allies failed to achieve any of their goals for D-Day itself: as well as Caen, Carentan, St. Lô, and Bayeux all remained in German hands. Only two of the beaches (Juno and Gold) were linked on the first day, and it wasn’t until 12 June that all five beachheads were connected. The battle to secure and expand the foothold took far longer than anticipated and the success of the operation was by no means the foregone conclusion that some would have you believe.

Lights all askew in the Heavens – the 1919 Eclipse Expeditions (Updated)

Posted in History, Talks and Reviews, The Universe and Stuff with tags , , , , , on June 3, 2019 by telescoper

Here is a video of my talk at the Open Meeting of the Royal Astronomical Society on April 12 2019. Was it really so long ago?

You can find the slides here: