Divers

[Robert Vermaat]

Passing river on air inflated skins was mentioned by a Rodian to Xenophons 10000. The idea was rejected.

Interestingly, the anonymous author of the late 4th c. de rebus Bellicis also proposed such an idea.

he is using an inflated skin to swim across a moat or a river

Yes, that was my first thought too, cf. the picture below. However, I think the man on the first picture appears to have something in his mouth. Nevertheless, it is indeed possible that he is not a diver but an inexperienced swimmer. Do you known any publications on this guy?

About this guy, how on earth would it be possible to float across anything sitting on that? It's instable - you'd fall off as soon as your feet don't touch the ground anymore.
I've inflated a lot of things for my kids - I know. :?
Now, if he would hang on to it with his arms, OK. But either the artist heard of it and depicted the technique all wrong, or the guy is doing something different than floating.