Schramm mystery ballista???

[Warhammer1]

Came across this museum pic of unidentified ballista (bottom right): http://en.wikipedia.org/wiki/File:Ancie ... Pic_01.jpg

Any information appreciated.

Thanx in advance.

Warhammer1

[D B Campbell]

That's easy. It's Schramm's Luftspanngeschütz, which was his version of Philon's aërotonon. At 77.9-78.26 (= Marsden 1971, pp. 152-155), Philon describes "what is called the air-spring catapult, being a stone-projector", which was invented by Ctesibius.

(I suppose someone should add the identification to the Wikipedia caption.)

[Eleatic Guest]

The caption is now complete.

PS: How are these springs in the bronze-spring catapult called anyway? In German, I think it is Blattfedern. Could it be that this is the very first technical application of this kind of springs?

[Koyuncu]

Here a good replica of aerotonon. It works pretty well.

http://www.youtube.com/watch?feature=pla...CYp8#t=664

Elastic Guest, Romans were capable of making steel springs for locks but apart from Rudolf Schneider's and Chevedden's claims Romans never used such metal springs to power their artillery.

Steel bows first reappeared in high medieval ages for crossbows but we should mentions that there was a strange catapult with two huge steel bows, used for projecting stones called Einarm.



Here, a good bunch of information about that strange machine.

[D B Campbell]

Romans were capable of making steel springs for locks but apart from Rudolf Schneider's and Chevedden's claims Romans never used such metal springs to power their artillery.

Of course, Philon claimed that it was possible to power a catapult with bronze springs (69-73 Thévenot = Marsden 1971, 138-147).

[Eleatic Guest]

Elastic Guest, Romans were capable of making steel springs for locks but apart from Rudolf Schneider's and Chevedden's claims Romans never used such metal springs to power their artillery.

Well, there are different types of springs and my question is if these bronze springs in Philo's Chalkotonon were leaf springs (disassembled view) and if they had other technical applications, too. I know very little about it, but it seems that such leaf springs were not the type of mechanism used in old locks.

[Koyuncu]

According to Ancient Engineers' Inventions;

Since we have a detailed description from Philon of Byzantium, we know that the construction of this weapon began with the forming of bronze leaves or folios (foils), which he called scales. Numerous allusions indicate that Ctesibius’ bronze springs only had two layers. The first secured to the opposing symmetrical layer by means of two pins, the second secured to the extrados of both, leaving the ends free.

Book's Reconstruction of Springs;



I have no idea how they got the information about number of springs but if this is the case then you may be right about lack of evidence about leaf springs.