Our new cheiroballista...

[Gaius Julius Caesar]

Nerva, ol' buddy, ol' chum! Calm down, Calm down....your are reading too much into other peoples comments, whats wrong with you?

Just out of curiosity, what exactly is it you do?
Do you have access to JRMES? I thought it was only for academics? If you have any published documentation, can you share it with some of us plebs? As you have obviously seen these documents, and translated the latin, it will be helpful for those of us who don't have access to and are unable to reqad latin if you could share this?
Not everyone had a classical education, but I think some of our brains are well up to the task of interpreting engineering.

BTW, has Alan made any progress on his repeater? I would love to see it working at higher power one day. I definately want one.

[Nerva]

Folks, I want to apologize. I'm usually pretty easy going, but I think some hot buttons were pushed, and I let my temper get the best of me.

Nerva, I'm sure you are a fine individual, and I think we should just "agree to disagree." I am sometimes wrong, I am sometimes right, particularly based on actual hands on work and study.

That is all for me. Dane

Salve Dane!

Fair play to you but, as we say here in Ireland, there were two of us in it :wink: I too am normally easy going, but I too must apologise. From my point of view, Alan Wilkins is a totally unassuming man. He has invested his life in this research and is always the first to admit his weaknesses. Right or wrong you have to admire that mans approach, he goes back to first principles and anybody who knows the man will tell you how humble he is.

I have no problem with people questioning Alan's research, but rightly or wrongly I detected a certain malice in some of the comments posted here. In any case I take my hat off to you Dane, at least one of us has common sense :wink: You say lets agree to differ and that's fair but I think you may have interpreted me wrongly. As I've said before, I'm neutral on the historical debate, all I ask is that any arguments are backed up by robust evidence which I admit I am not in any position to provide.

As to Magnus, I always remember my fathers words...There's a world of difference between a good education and intelligence

Angle, I think I have already explained my motivation, critisise Alan all you want but be professional about it. As for what I do, well I'm a drug dealer :lol: Actually my doctorate was in an obscure field of particle physics but I'm working as process control engineer working in the biopharmaceutical industry (are you suitably impressed? my wife is not :roll: ). I also lecture in particle physics at a local university so I have access to JMRES etc. which is probably why I'm so anal about proof and evidence.

I have seen some recent interpetations of the classical texts which amaze me in their accuracy but, you will have to wait until Alan publishes his next work to see. You are dead right about an engineer being able to make a good assessment of it but, and here's the kernel of it, unless you are working from an accurate base line your are wasting your time. I guess what I'm trying to say is that sure, you or I could have a fair crack at building a machine if we had a good set of drawings etc. But in this case the plans are in a foreign language, so first we need an accurate translation, and unless the translation is correct we're wasting our time.

Anyway, I've said enough, time to go back to bed and snuggle up to my ballista catapulta thingy wingy yoke...love you dear...

Anyway, fair play to Dane.

[AuxArcher]

Martin, if we ever meet in person at some event, I'll buy you a stout or three. A friend once said never trust any beer that you can see through, and I tend to agree Some ales also fit that criteria.

Do you happen, or does anyone else who reads this feel that Marsden's translations can be fully relied upon? If not, though I don't read Greek or Latin, perhaps commissioning a scholar to translate Heron, Philon, Vitruvius, et al, would be worth while. If Alan has made available his translation, is it available in a scholarly journal in full?

A big, big future project, if it ever comes to fruition, is to build a torsion machine entirely with Roman and Greek era hand tools, such as block planes, draw knives, pit saws, etc, cast bronze parts using Roman period techniques (one blacksmith told me that perhaps clay molds were likely used) using period alloys, sinew or horsehair ropes, and so on, hand wrough iron plating, etc. Methods available must impact processess developed and used in building any ancient machine, I am guessing. Just saw the carpenter's tools thread with those yummy reproduction Roman hand tools, and that gets the juices flowing for certain.

My own preference is for the early machines, I find those so facinating, rather than the late ferroballista (excellent term, Randi) machines. The little gastrophets are very cool to me, and that is actually much closer to start date than the future project mentioned above. You will probably never find me building a metal framer, simply because I don't possess the competent metal working skills. Since a lifetime can be devoted to wooden machines, I don't shed many tears. And above all else, what I am striving to do is not improve upon these designs, but find out what they really were capable of. I dont think anyone has pulled off sinew ropes yet, and I hope to change that.

Dane

PS Attached is one shot of my little baby, a "scorpio-minor" made from ash. The plating is not iron or bronze, alas, but cartridge brass. Pardon the black PVC washer mock-ups. The real ones will be bronze. The slider I am going to redo, as well as some other modifications.

[Magnus]

Let me just remind everyone as well that had this debate taken place in real life, none of the tempers would have flared up. This is one of the inherent dangers of text only communication.

Thank you all for stepping up and showing a great deal of maturity.

[Kevin J. Aschenmeier]

Wow.
What a debate! I lost sight of the topic.

Just a quick note on languages. I built a scorpio maior. I read classical greek and latin. I found the only way to build the machine in a way I was happy, was to constantly refer to the original texts plus the numerous publications on recent finds.

All builders will be faced with the same problems. They will have to fill in missed parts, or interpret others. The catapult texts are not like a modern set of blue prints. Some of the documents are horribly corrupt. Some of the words the ancients used are totally confusing. I doubt that the original authors would have thought thier texts and knowledge would be lost for 2000 years until such people as Schramm and Marsden, and Alan Wilkins and all of us came along. They probably were writing for people who were quite familiar with thier machines, or ones similar so they could brag about thier own improvements.

Good luck to all builders.

Kevin

[Gaius Julius Caesar]

[quote="Nerva Salve Dane!


Angle, I think I have already explained my motivation, critisise Alan all you want but be professional about it. As for what I do, well I'm a drug dealer :lol: Actually my doctorate was in an obscure field of particle physics but I'm working as process control engineer working in the biopharmaceutical industry (are you suitably impressed? my wife is not :roll: ). I also lecture in particle physics at a local university so I have access to JMRES etc. which is probably why I'm so anal about proof and evidence.

Anyway, I've said enough, time to go back to bed and snuggle up to my ballista catapulta thingy wingy yoke...love you dear...

Anyway, fair play to Dane.[/quote]

Right professor, by the way the name is Angel, remember it!
:wink:
As to being at the mercy of translators, that is something we all have to live with. Are you willing to share any of the publications you have access to? :|
And while I find your credentials impressive , no I'm not impressed.......When the drugs and poltices the doctors prescribe for every thing actually cure what they are prescribed for, then I will be impressed.
I have to much real life experience with engineers to be in awe of them. :wink:

And btw, don't go accusing me of criticizing anyone, believe me, if I decide to criticize anyone, I will, and they will be in no doubt about it. Now put your handbags away and be nice.

See you at Corbridge. :mrgreen:

[Nerva]

Do you happen, or does anyone else who reads this feel that Marsden's translations can be fully relied upon? If not, though I don't read Greek or Latin, perhaps commissioning a scholar to translate Heron, Philon, Vitruvius, et al, would be worth while. If Alan has made available his translation, is it available in a scholarly journal in full?

Salve Dane

From what I've seen, the original works contain many side notes and comments. Perhaps added by the original author perhaps not. It would appear that there is as much information in these often cryptic notes as there is from the original texts. Unfortunately much of what we have to rely on are medieval texts, "copies?" of the originals. After countless copying down through the centuries things eventually get lost in translation, so there is no complete source that survives to this day.

As for Alan's work, I will post up a full list of publications later. One criticism I have made directly to Alan is the fact that he has not produced a single comprehensive publication of his work as Marsden did, so let’s hope one day he does. Just a minor point though. In one of your earlier posts you made mention of Alan and a BBC production. That’s a very interesting story. When you do television work you basically hand over control to the producer. For example, Alan had serious concerns over the construction of the arms and in particular the spring frames. He implored them to use iron cladding which they totally ignored, but you don’t see this in the finished production.

Another fine example of this is a program Alan and Tom Feeley did for the History Channel last year; I think it was one of the Ancient Discoveries series. Here they demonstrate both a manuballista and a 3 span. While the film shows a 3 span firing a number of bolts, the voice over constantly refers to the machine as a cheiroballista, Tom has to cringe every time he watches it :oops:

A big, big future project, if it ever comes to fruition, is to build a torsion machine entirely with Roman and Greek era hand tools, such as block planes, draw knives, pit saws, etc, cast bronze parts using Roman period techniques (one blacksmith told me that perhaps clay molds were likely used) using period alloys, sinew or horsehair ropes, and so on, hand wrough iron plating, etc. Methods available must impact processess developed and used in building any ancient machine, I am guessing. Just saw the carpenter's tools thread with those yummy reproduction Roman hand tools, and that gets the juices flowing for certain.

Now that would be a fantastic project.

The little gastrophets are very cool to me, and that is actually much closer to start date than the future project mentioned above.

I cannot see why more of these have not been built? A beautiful machine.

I don’t think anyone has pulled off sinew ropes yet, and I hope to change that.

I don’t know if you’ve ever watched the history channel program called "Weapon Masters"? I'm not a fan of the show but I did watch the episode where they reconstructed a catapulta "modern" style. While the concept of reconstructing a machine using modern materials and techniques does not appeal to me, they did some excellent experiments with various spring materials. They used a sinew rope, a horsehair rope and a few other natural as well as synthetic materials. The results were very interesting. One problem with the sinew was it's modulus of elasticity. Every time you tensioned the spring it continued to stretch resulting in a continuous loss of power. Of course this could be down to the technique use to construct the rope as much as to the material itself.

PS Attached is one shot of my little baby, a "scorpio-minor" made from ash. The plating is not iron or bronze, alas, but cartridge brass. Pardon the black PVC washer mock-ups. The real ones will be bronze. The slider I am going to redo, as well as some other modifications.

While we differ on the use of springs on such a machine, I must complement you on your craftsmanship: wink:

[Nerva]

:oops: :oops: :oops: Sorry Byron, I must apologise for using your last name insted of your first, I got it mixed up and I didn't mean to use your sirname like that, sorry Byron :oops: :oops: :oops:

[AuxArcher]

Nerva, thanks about my craftsmenship. Now how will it perform? It will look awesome in parades, too!

What do we have today? The texts as we are now stuck with them , actual artifacts found at various sites (washers, components, the Xantan frame, etc), and iconographic evidence (Trajan's Column, tomb stones).

I wonder how much we are missing, and how we are interpreting or misinterpreting things? Would Heron, could you bring him to the present, say "good job" or "What the heck is that thing?"

I also wonder how our work will be compared to what is being done 100 or 500 years from now, if anyone still cares about 2,000 year old technology then.

Nerva, I know from experience with sinew that it has enormous stretching properties, and weather can severely affect it. A catapult will perform I am guessing more sluggishly during times of high humidity, rain, etc. than a hot, dry summer day. Wood of course is affected by weather conditions, temperature, and so on. Animals can eat your sinew if you are not alert, as well. I know for this for a fact, as my pug tried to steal a nice leg sinew. I felt so bad taking it away from her.

Regarding how a rope is constructed, not too many options, eh? One is reverse twisted individual fiber plies, made into threads, then yarn, then strands, then rope using a rope walk or other simple machinery. My own rope jack is very simple. Braiding is the other way to do it, I believe. I am still wondering which way I should go for my horsehair rope. Anyone have suggestions there? Reverse twisting or braided?

Dane

[Gaius Julius Caesar]

Would braiding not put undue stress on the fibres, especially if it was horsehair?
I dont know what sinue would do though?

[D B Campbell]

... cast bronze parts using Roman period techniques (one blacksmith told me that perhaps clay molds were likely used) using period alloys ...

Roman washer moulds were discovered at the Auerberg, so your blacksmith friend is quite correct, Dane.

(P.S. Phew -- I'm glad I missed most of this thread; I might've come away with a black eye or two. :wink: )

[Nerva]

Salve Dane!

Do you have a copy of Marsden's "Greek and Roman Artillery - Historical Development"? If so go to page 87 chapter IV Range and Effects. In the second paragraph Marsden talks about spring materials although he makes no mention of how they were constructed. I cannot vouch for his accuracy but might be worth checking out. In the same chapter he also quotes the ranges of Schramm's machines. Schramm used braided horsehair which is interesting.

Vale

[AuxArcher]

Salve, Nerva. I do indeed have both Marsden volumes, and my wife wonders why I read them so often She is a English professor, which may explain much. I'll re-read that section you mentioned after work today, and thanks for the pointer.

I'm thinking braided would be easier to make, but reverse twisted rope may perform better, at least using horsehair. That is based not on scientific proof, but my instinct. They may act the same way in a torsion spring...I just don't know.

Once I actually get my rope jack out and make the rope, I will post photos, sometime this summer. I have access to a big wooden pavillion which will be ideal as a makeshift ropewalk. Rope is an interesting thing all by itself. Cordage is highly underappreciated...until one needs to tie something off. Primitive cordage made from plant fibers such as dogbane is really a lot of fun to make, too.

Duncan, I have a few strong bruises myself, self-inflicted mostly Do you happen to know if there are photos or drawings of those molds? I'm using sand molds for now, not Roman perhaps but I have some experience already making sand molds, so the learning curve is not so steep. I have the patterns pretty much all made up out of all kinds of materials, and will use a sand core when I cast the washers. The metal I am using is silicon bronze, but my understanding is that modern US pennies are similar to ancient bronze alloys (this I was told, and may not be right).

Dane

[derek forrest]

This is certainly a debate of some antiquity but the basis for my argument is Bernard Jacobs who looked at Alan Wilkins' machine and indeed discussed it with Alan and then tried to construct the manuballista using all of Heron's measurements. He did so and then wrote an article in 1998 in Exercitus. Aitor came along later and then made a similar machine but as an inswinger and I think I can remember Bernard conceding that as a possibility.
I appreciate that this meant 1" washers but the proof of the pudding is in the shooting. It is definately not a toy and nor is Aitors'.

[Nerva]

I'm thinking braided would be easier to make, but reverse twisted rope may perform better, at least using horsehair. That is based not on scientific proof, but my instinct. They may act the same way in a torsion spring...I just don't know.

I would have to agree with you. You can produce a denser rope with twisting. This means you can probably get a greater volume of material into the rope and hence store more energy. As with all substances though it boils down to the tensile properties of the material. I do not know the specific modulus of horsehair but if the sheer strength is superior to its tensile strength then braiding would work better. I cannot remember what why Chad Houseknecht constructed his rope on Weapon Masters.