I have no clue what a siegure is but I don't think it will entice me to make with the siege enginery:) Besdies your textbook case of A.D.D. would end up witht he damn onager half assembled in the backyard anyways.

i can offer a possible starting place for your project.  (first, a short disclaimer: i do not advocate, recommend, suggest, imply or in any other way endorse reading any further; should you choose to ignore this notice, i will not be responsible for any damage, injury, hurt, disappointment or regret--inconsequential or inconseigural--resulting from your actions).

use an empty 5 gallon plastic water bottle as a bat to hit a citrus fruit (orange or grapefruit) ball.  pretty cool huh?  (its also cheaper than using a beer bottle to drive golfballs). 

this concept might just lead to the 'soul of a brand new seige machine' that looks outside the box & into the empty container to provide hitherto untapped sources of propulsion.  

You need to give a few details. Is the besieged city walled? Do you care about the inhabitants? Are there hills around the city?

One option is the Trebuchet. It is not entirely portable, but somewhat target able. I would also suggest (if the inhabitants do not matter) Greek Fire.

http://nfo.edu/trebuche.htm

You can knock down buildings that are inside the city. However, you will need men to defend the engine.

IG

You need to give a few details. Is the besieged city walled? Do you care about the inhabitants? Are there hills around the city?

I think he just wants to fling a cow.

Then the treubchet is the answer. The cow will enjoy the flight, but it will not like that sudden stop at the end.

IG

Then the treubchet is the answer

Presonally I am partial to the onager for ease of aim. Getting the release point on the trebuchet is quite tricky.

So, a choice between a cow and "Greek Fire." (Is that some sort of gay slang that I don't get?) I'm pretty sure the inhabitants of the building do not matter, and I'm also fairly certain we can find some "men" to "defend the engine."

A definition:

Greek Fire was the secret weapon of the Eastern Roman Emperors. It is said to have been invented by a Syrian Engineer, one Callinicus, a refugee from Maalbek, in the seventh century (673 AD). The "liquid fire" was hurled on to the ships of their enemies from siphons and burst into flames on contact. As it was reputed to be inextinguishable and burned even on water, it caused panic and dread."

IG

Sorry. Forgot the sarcasm tags. (Greek Fire was yet another thing I learned about through roleplaying games.)

Presonally I am partial to the onager for ease of aim. Getting the release point on the trebuchet is quite tricky.

Interesting. What is the difference between the "tre" and the "ona"? Distance? Throw weight? Does the aiming ease lower the throwing stability for higher weights?


IG

Onagers are much simpler to aim as the throwing torque is basically the only variable. With trebuchets you have the counterweight and the sling release to worry about (or int he continuous cycle treb you have to time the latch pull just right). While the trebuchet can atain higher weight and much greater distance, I think the ease of construction and simpler aiming dynamic make the onager the choice for mideval mass destruction.

I think he just wants to fling a cow.

Run away !!!!!! Run away !!!!!

Sorry, CS I just got it.

IG

Cows would make for nice plague bombs.. pretty sure animal and human carcasses were used in this manner during the crusades but I am too tired, sore, and sick to google for it now.

At the very least, my roleplaying game education says you're correct, grey. I've also heard it referenced as "the first version of biological warfare" either in basic training, or during some sort of training from the likes of SPC Lowkee or SGT Pyramid.

At the very least, my roleplaying game education says you're correct, grey.

It was also my experience in tabletop an history that led me to this conclusion. in that time frame "more" was always better..... (for siege engines)