Sunday, August 28, 2011

Fall of France, 11: Making Free On The Land: Or, the Bailey Bridge

The Kriegswissenschaftliche Mémoiren collection of the War Archives of the Austrian State Archives contain many interesting and well-produced, even beautiful manuscripts. So many, in fact, that I've argued that you need some kind of sociological explanation to account for them. Disappointingly for those who want to raise the credibility of the whole military-intellectual racket, I found little of interest in the ones that dabbled in high philosophy. 

The technical manuals, on the other hand, are awesome. They all need to be digitised somehow and put on line. We just don't get how good those old guys were at doing stuff, because we don't understand the problems they solved. It's a lesson that historians of technology need to hammer home again and again until history finally takes cognizance of  the way that doing stuff --for example, moving artillery or 30 tonne tanks across country-- was, and is hard, and calls, and called upon, a substructure of skills and experience. It strikes me as a truism that that substructure is going to look like, and must look like, the everyday economy at work. 

That, for what it's worth, is the epiphany I had when looking at Lieutenant-Colonel Ano Turpin's two-volume treatise on artillery. (I'd like to know more about this guy, but there are all sorts of real and possible transcription problems here. Turpin may have been active in the 1720s or the 1770s. I'm thinking that "Ano" is  an abbreviation of "Antonio," and that his being a Piedmontese officer explains the Italian form of the personal name and a not-uncommon French last name. But I'm not overly satisfied with my conclusions.)

So what does Turpin have to say? That the well-known distinction between field and siege artillery is actually between "meadow" artillery and static. I'm translating freely back and forth here, just the way that a guy named Obristleutnant Antonio Turpin did, and I'm getting that "meadow artillery" gets thrown across the country so easily that commanders had to be careful that they didn't end up in a position where there wasn't enough grass around the feed the gun teams (contemplate for a moment what that means about the state of the roads and of the countryside round about), while  moving siege artillery is part of that project of moving things that aren't supposed to be moved. Imagine those massive teams and specially built bridges and whatnot that were required to move despoiled Egyptian obelisks, giant church bells or purpose-cast floodgates.

People move around easily. too easily, and end up places where they don't want to be. Armies only seem to do the same, and in reality must prepare in advance and tap into the contemporary transportation industry. But what if that industry is itself in flux? What if horses are going away and the semi is just being born? Then the times are out of joint. We really need to do a better job of fixing ourselves to times and context and understanding how human intervention has changed the landscape. Because our relationship with the landscape might go a lot deeper into our cognition than we entirely understand. 

Or we can just put the Royal Experimental Bridging Establishment to work. (This is funny and creative. I thought about embedding "Bridge Over Troubled Waters," but that would just sad. And by sad, I mean "pathetic.")

So here's one way of putting the story: a bad picture of a bad photocopy of an illustration in Ralph Freeman and Alwyn Edward Long, "The Erection of Military Bridges, 1939--1946," 411--39 in The Civil Engineers In War. Look for it mouldering in your local engineering library. Freeman and Long have written an odd article here. They think, probably correctly, that the bridges that the Royal Engineers (Transportation) erected after everything had been figured out were more scientifically interesting than early improvisations, so this article about wartime road bridge building is mostly concerned with the ones erected in the Occupation Zone to replace bombed-out and demolished structures. There might still today be some small audience for such things amongst civil engineers and perhaps historians of technology writing dissertations yet undreamed of, but there's not as much here as there could be that's actually interesting to the historian of World War II, much less the Battle of France.
This picture, which is alleged to show the extended Bailey Bridge at Gennep, Holland, is a different matter. The bridge is, I guess, the long line in the middle of the photo. What interests me is the landscape around it. That's what happens when the retreating Germans open the sluice gates. That's the landscape of war.

In an article published in the interwar period in the Army Quarterly (I photocopied it but forgot to take bibliographic information, and keep forgetting to commit the time to remedy the error), another Lieutenant-Colonel, E.St. G. Kirke discusses  "Railways in War." Kirke believes that railways are indispensable in modern warfare, and that therefore engineers are going to have to know how to run them. But, he also points out that at no point during their advance into France in 1914 were the Germans more than 50 miles from the nearest railhead. This was because the French (and, I guess, the Belgians) were ill-prepared to demolish their rail network. 

By 1918, the lesson had been learned, and German demolitions behind their retreats presented the Allies with a severe challenge. All the replacement bridges, Kirke notes, were built with demolition chambers. There might be problems in carrying enough demolition stores to knock them all over, which is why the RE first goes in for the industrial-scale production of RDX (note ridiculously incorrect historical account) during the late pre-war, but no-one can fault the bridge builders. And, it follows, in future wars, military logistics will have to take into account a requirement for massive bridge repairs. 

Later in CEW, Follenfant and Watson* spell this out. During the campaign in northwestern Europe, 122 railway bridges were repaired or built; 346 new bridge spans were erected; 47 old spans were repaired; 20,324 linear feet of bridging was constructed or repaired; 1,030 route miles (1,632 track miles) of damaged main line were repaired; 34 miles of new track line laid in depots and 29 on main lines; and 501,000 cubic yards of earthworks carried out. This is a classic example of "numbers that are bigger than other numbers, which are smaller" rhetoric, but I justify including them to myself on the grounds that they give a sense of scale.

Now, this concerns railway bridging. The British military engineering establishment developed a limited suite of modular railway bridge repair components, but even they mostly depended on big old pieces of steel straight from the factory, an approach that worked well enough for the Germans and which the Americans adopted soon after they got on shore. It would have been cool if Bailey bridge components could have been used to build new railway bridges, but I gather that that's asking too much of reality.

What concerns road bridging was first laid out by Bailey himself and his co-authors in their own contribution.** And I should confess a personal investment. This is the bridge that the schoolbus (and sometimes me on my good old Suzuki GT500) used to cross twice a day in high school.

Picture by user "Cabin Boy" at Fishing Vancouver
It's a single-single Bailey bridge set on the road to Port Alice. It's been there since 1975, when the original two-lane timber-trestle bridge washed out, and probably will be there for a while yet, because it's really not that important a part of the world. (The best that I could do for local topicality.) The planked deck catches your motorcycle's wheels and makes them wobble. It's not dangerous, but it is disconcerting.

Donald Bailey began working on what became the Bailey Bridge... at some point. Nineteen-forty is often mentioned, but the engineering establishment had been looking for new bridges since at least 1937.*** The problem as phrased then was memorably illustrated by noting that the heaviest load that the British army's bridging train had to deal with in 1914 was the standard chuck wagon, which was rather heavier than the 60 pounder. By 1918, it was the 9.2" howitzer.  Now, this evolution might seem a little bizarre, given that the 9.2" weighed over 5 tons. If you read Lloyd George and Winston Churchill, you'll encounter the quite disingenuous claim that the army had to go to big guns to attack German  dugouts. Actually, it was a matter of range, and for a very telling reason. The last iteration of the 9.2" had 14,000 yards, versus an absolute peak of 11,000 yards extracted from much ginned-up 18 pounders. The army wanted 15,000 yards on the assumption that rivers requiring bridging are about 2 miles apart in northwestern Europe, and this range meant that troops could exploit out of a bridgehead across another river without bringing big guns across congested rear-area bridges. (This would be Bidwell and Graham, unless it's not. I'm afraid to look this factoid up, because I suspect that I won't find it there, and will be sent to the stacks to dig around in back issues of Army Quarterly. And as much fun as that is, I don't have the time!)

It's all about the bridges. So bring it forward to 1937, and we find the British army was using a number of sets. These included a design derived from General Martel's "canal lock" bridge, described as an equipment allowing 12 ton "independent tanks" to cross the canalised rivers of northwestern Europe at the locks, in the event that the existing bridgeswere destroyed; another was derived from an earlier modular bridge for civil engineering practice, the Callendar-Hamilton, not so well optimised for being erected and launched under fire; and a yet earlier bridge set that had been, with difficulty,  improved to carry a maximum of 24 tons. The thing is, the army wants 40 tons. The time is past when chuck wagons are the biggest load the army has to move. The 9.2" was an anomaly, but a bigger load has come to stay: the assault tank.

Now we stop and reflect. The British army is about to commission a major industrial effort involving subcontracting to 600 firms. It is going to modestly undertake to transform the steel industry by halving the allowable range of carbon in manganese alloy high-tensile steel to allow the welding of certain Bailey bridge components to high tolerances for modular construction. It's going to institute product control so precise that American industry actually couldn't do it, at first. And yet at the same time, the Red Army was specifying a 30 ton tank, and the French were fielding one. But this does not actually contradict the point. The Red Army bid up the weight of the T-34 looking for features that would allow it to ford rivers in spring and cross on the ice in winter. This meant height to the deck and low ground pressure, and they ended up building a pyramid on their wide-based chassis, and that famous, well-sloped glacis.

 Meanwhile, the French built their CharB1 on the assumption that it would be delivered into battle by the French rail network. It would cross rivers on rail bridges, and, and this is important, it would be unloaded at train stations. This directly implied that the French would control their own rail network. They would be able to seal off stations and create deployment areas where they could bring their armoured assault divisions into battle. It's as Janis Langins argues: The French state is built, and conserved, by its military engineers. The fortress, and its associated transportation network, structures the French state.

Conversely, if the cavalry fails to cover the fortress network, the French state is hooped. And, as we know, the British, possessed, historically, of the best cavalry in western Europe, failed to do their job in 1940. (Actually the Yugoslavian Army, but what can you do?)**** There's lots of reasons for this, but one of them is that Donald Bailey is beginning his work this year, rather than ending it.

*Henry George Follenfant, and John Douglas Watson, "Military Railway Construction, Part III: Construction and Repair in North-West Europe, June 1944 to May, 1945," CEW 2, 591--628: 625.
**Sir Donald Cameron Bailey, Robert Arthur Foulkes, and Rodman Digby-Smith, "The Bailey Bridge and its Developments," CEW 2, 373--68.
***Article in the Journal of the Institution of Civil Engineers. I'll dig up the reference if anyone is interested.
****[Edit]: While I was throwing out digressive footnotes, I added one about the bagpipe scoring on that Youtube video of the charge of the Greys at Waterloo that I linked to. The "bagpipes" that are, on second listen, strings. Oops. Never mind, then.  


  1. Another great article. Thanks for writing- and researching- it. Your ideas on geography and history I find fascinating.

  2. Post-1945 France often seems to be structured by its aviation engineers. Dassault builds the sinews of foreign policy and thereafter foreign policy serves Dassault.

  3. Thanks, Chris.
    Yorksranter: Well, it is hard to be about the fortresses after this.
    No. Wait. I meant this.