Comments on Onasander, which turned up a surprising experiment in ancient explosive bullets.

Hot Sling Bullets

Muzzaguchi

I was reading Onasander (as you do) and a passage intrigued me so I thought I'd ask here.

19.3 'The sling is the most deadly weapon that is used by the light armed troops ... not only is the impact itself violent, but also the missile, heated by the friction of its rush through the air, penetrates the flesh very deeply ...'

Lucretius (6.306) and Ovid (Metamorphoses 2.727 and 14.825) also mention the heating of sling bullets.

I just wanted to ask reenactors with experience of slings if this was the case. Something to do with the transference of kinetic energy probably if they are heated.

Mithras

I sling every week and I never see a cloud of steam erupt from the water as my sling stones hit!

You could theoretically heat up lead glandes before shooting, but that would knacker your sling after only a dozen shots - plus I would wager the 60 mph journey through the air would only cool the glandes.

Flavius

Onasander is the greek author of a treatise named Strategikos or De optimo imperatore describing the duties and the skills of a good military commander (first century AD).

The heating of a sling bullet is obviously an exaggeration, since the friction with the air can produce heating just with very high speed (around sound speed) of course impossible to get.

Anyway Caesar (DBG, IV, 43) mentions hot terracotta bullets used by Gauls to set fire to the barracks of a roman camp during a siege.

Cordvs

I have some experience with hot slingshot if you’re interested. Though I too can’t see how they could heat up in flight.

In my opinion the air-resistance that would cause them to heat up would also slow them down real fast.And they don’t have an independent means of propulsion.

The terracotta slingshot mentioned by Caesar were heated in a fire specifically for this purpose.Haven’t tried that one but it sounds reasonable enough.

But there is also something I know from my own experience. There was this battle in Velsen (NL) when slingshot was, by the looks of it, used immediately after casting.

While once trying what rate of fire this would give (it was astounding actually) we found that, when we really got the hang of it, the bullets sort of exploded on impact scattering hot bits of lead around. We worked as a team, casting lead into fingertip-moulds in wet sand (the wet sand cooled the exterior real fast), put it (with a pair of tongs) straight out of ground into my (wet) leather sling and then throw. Apparently the interior of the slingshot was still hot and semi-soft when it hit the wall causing it to distort and break up.

So I can imagine instances where slingshot would be hot, even scorching, but I don’t see them heat up in flight.

Come to think of it, where there instances where the ancients would even learn of air-friction ? Could this be a translator embellishment about hot slingshot ?

mcbishop

Heating through air friction is, I believe, negligible at subsonic speeds (and at greater than the speed of sound more a result of the pressure wave than actual friction). Notions of friction and the properties of air were common amongst Epicureans, epitomised by Lucretius, but they tended to think of it in terms of particles rather than as a fluid (interestingly, an argument that still surfaces in heated :-) discussions over aerodynamics and the precise significance of Bernoulli versus Newton).

In short, I don't think this is a translator embellishment; they really believed it. If you doubt the observational abilities of the ancients, remember that the oldest boomerang is something like 23,000 years old and its successful design, construction, and use required an understanding of the airfoil, asymmetric lift, gyroscopic stability, and gyroscopic precession. I'm willing to forgive the Romans a few odd notions about friction ;-)