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Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

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Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#3
Yep, unless he weighted himself down with bags of rocks which is possible (dive weights), the bag would be too buoyant and he would not be able to swim downward to depth. He would likely need ropes or straps to keep the bag to his body, instead of struggling to keep the bag from slipping away.

Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#4
post #2

He's swimming on the surface. That bag would be too buoyant for diving.

Why have an inflatable goatskin that you're inhaling from for swimming on the surface? Considering the fish next to him it seems more likely the artist left out the boring aspects of holding rocks or whatever to reduce buoyancy.

Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#5
post #2

He's swimming on the surface. That bag would be too buoyant for diving.

Yep. One of the first issues you'll encounter when learning to dive is getting your body to sink (that's what all those lead weights are for). I also don't think an inflatable goatskin has enough air capacity to be relevant.

Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#6
post #2

He's swimming on the surface. That bag would be too buoyant for diving.

Additionally, a bag of air of that volume would not give much time underwater - maybe an extra breath or two. The extra effort and drag of carrying the bag would make it less effective than just diving.

A modern steel SCUBA tank is typically pressurized to 200 bar, or about 3000 psi, making it 200x more useful than a bag. An inflatable ball is only inflated to about 0.5 bar/8 psig, human lungs are only capable of about 0.1 bar/2 psi. This would be about as useless underwater as one of those little one-liter bottles with integrated mouthpiece that scams show being inflated with a bicycle pump...

Still cool to see swimming like this depicted in 800BC! Puritan attitudes towards swimwear as well as imperial navies conscription of non-swimming sailors seem to have caused us to imagine swimming as a modern activity that we do better than anyone in history, but I expect that people throughout history did lots of swimming.

I also find it interesting that he's depicted wearing a helmet, I wonder if that's to identify that "this guy's an Assyrian foot soldier" or if they actually swam in their helmets!

Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#8
post #2

He's swimming on the surface. That bag would be too buoyant for diving.

Additionally, a bag of air of that volume would not give much time underwater - maybe an extra breath or two. The extra effort and drag of carrying the bag would make it less effective than just diving. A modern steel SCUBA tank is typically pressurized to 200 bar, or about 3000 psi, making it 200x more useful than a bag. An inflatable ball is only inflated to about 0.5 bar/8 psig, human lungs are only capable of abo…

> This would be about as useless underwater as one of those little one-liter bottles with integrated mouthpiece that scams show being inflated with a bicycle pump...

These irk me too! The pictures never mention that the hand pump in them, isn't a bike pump at all, it's a high-pressure pump that you will have to pump for nearly an hour. I see these constantly in the "suggested products" when shopping for any diving kit on amazon.

Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#9
post #2

He's swimming on the surface. That bag would be too buoyant for diving.

Why have an inflatable goatskin that you're inhaling from for swimming on the surface? Considering the fish next to him it seems more likely the artist left out the boring aspects of holding rocks or whatever to reduce buoyancy.

Artists don't always use realistic perspectives, especially not that long ago. The swimmer isn't inhaling, he's blowing into the goatskin to keep it inflated. It's just like a modern inflatable life vest which has a manual inflation tube to use if the automatic inflator fails. There are no rocks (although ancient free divers sometimes did hold rocks to dive down faster).

Re: Assyrian soldier diving with an inflatable goatskin bag (ca. 865–860 BC)

#10
post #2

He's swimming on the surface. That bag would be too buoyant for diving.

See the first reply.

> Another possible explanation for the above scene is that the soldier is helping himself to float by blowing into the goatskin, which is therefore a sort of floating device.

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