Heron of Byzantium put a lot of effort describing this rather peculiar device in his treatise on sieges but he didn't say anything about why one should make a ladder out of leather and then inflate it to scale a wall instead of just using a normal ladder.. What do you guys think are the pros of this kind of siege engine compared to wooden ladders aside from being easier to bring along with an army?

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Also interesting is the use of a net to scale the last part of the wall instead of just making the ladder longer. Although it could be that an inflatable ladder isn't strong enough to be longer than a certain length the Heron also advices you to do this w [ Download ]

I think the sturdier the ladder, the quicker it would be to climb it, and the larger the chance of success.

If it were even possible to make a leather ladder so that it is more or less air tight, it would still be really hard to climb one. Let alone when the enemy would be shooting at you.

I don't think we should dismiss historical texts like that, especially not manuals like this one which was specifically made to inform actual soldiers on how to conduct siege warfare. Making a ladder out of leather is clearly more labour intensive than wood so they clearly wouldn't do it if it didn't work. In spite of that, Heron includes this contraption in a text that is supposed to teach very little above the basics of siegecraft.

For ease of reference, the text runs

Quote:

Making ladders of hides we shall bring them to the wall; these are stitched like wineskins and, smeared around the stitches with grease, f illed so as not to def late. For when they are inf lated and full of air <and> kept from def lating, they necessarily become upright, held f irm for climbing by the air. But if the wall should be higher than the ladders, they are placed beneath ladders of tow which are constructed by being bound together with plaiting and stitching, net-like, similar to the so-called soldiers’ packs. Hooks are attached to the ends of these <nets> so that when thrown from the leather ladders placed beneath, they catch on the merlonsand thus facilitate the ascent of the wall at will. The drawings of the ladders are delineated

We should also be cautious that the treatise here is referencing a far earlier work by Philo Mechanicus, so the invention may not be a current weapon but referencing experiments of a great engineer known for work on pneumatic and hydraulic devices.

An inflatable siege ladder?
Can you see the people on it bouncing around and struggling to stay steady as bags move an wobble.
It'd be like something out of a game show.

That's before we get to the wear an tear on from men in armour climbing all over it and when some one will throws, shoots or drops something sharp it will pop the lot of them.

Really why not use large wicker baskets an stack them up? they could be solid and light enough to carry to the wall an climb quickly.

Various interesting designs for collapsible ladders do seem to have been a common feature of late medieval/early modern "war books", although I can't say I've come across an infatable one before.

http://manuscriptminiatures.com/5728/21010/

http://manuscriptminiatures.com/5728/21009/

https://i.imgur.com/wzyzydx.gif

On the other hand, there are examples of leather being used to create air-tight, inflatable devices. Here's Peter Whitehorne's description of an inflatable girdle, which is very similar to devices illustrated in a number of 15th century manuscripts:

https://i.imgur.com/2diYbTb.png

I'll have to double check but i think Pietro Monte even uses a similar language of "stiched together like wineskins" as your source when describing his floatation device.

That said no I'm not quite sure what the advantage of an infatable ladder would be. My only guess would be that after being inflated the advantage would be it's rigidity over just a collapsible rope ladder. You would probably need somone with some pretty strong lungs to get it rigid enough to actually support someone's weight. Though it might be like jean suggests that the idea was that it just had to be rigid enough to push a hook up to the top of the wall, and afterwords would just be supported by tension like a rope ladder.

Edit: just noticed your attachment. huh, he's definitely standing on the top rung of a leather ladder. i guess we'll have to go with the strong lungs theory.

I can't speak to this specific device but for context, I have few observations.

I think we should indeed be careful about these kinds of manuals, and at the same time not be too credulous but also not be too dismissive. In academia the tendency in the last 150 years or so is to err on the side of assuming it's all fantastical nonsense. I am not an expert on Classical engineers but I do know that they were brilliant people whose seemingly fantastical ideas did come to fruition. Look at the Antikythera mechanism. It may or may not have been made by Archimedes but somebody back in his day conceived, designed and put that thing together and it represents technology far more advanced than we had ever given people in that time period, or for many many centuries later credit for achieving.


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When it comes to the late medieval and Early Modern kriegsbücher, starting with the Bellifortis and progressing through the likes of philipp mönch and Talhoffer, and the equivalent military engineering manuals ala Taccola, Giovanni Fontana etc., it's quite clear that they contain both fantastical or theoretical concepts as well as quite real ones that were actually made and used in warfare, and the preponderance were of the latter variety. We still don't know what a lot of them actually are, but one by one tests and further research are revealing that they are in fact turning out to be real, viable designs and some have been hiding in plain sight so to speak for generations.

Guys like Heron and Archimedes, and Ctesibius and Philo of Byzantium and so on were genius mathematicians whose designs changed world history. An inflatable siege ladder doesn't make any sense to me on the face of it, but then again neither did the Zwerchau when I first read the Zettel.

Just my $.02

I have not read Heron of Byzantion recently. But aside from what Jean said about the need to mix practical engineering with weird stuff to get attention from a potential patron, a good article on how hard it is to figure out how the manuscripts we have relate to what the original author wrote is P.H. Blyth, "Apollodorus of Damascus and the Poliorcetica" in Greek, Roman, and Byzantine Studies 1992