[SunkenCiv]

A Roman shipwreck, dating to the third century AD, has revealed signs of smuggling. [Sebastiano Tusa]

[Ken H]

They bought these small tubes cheaper in Africa, hid them everywhere within the ship, and then re-sold them in Rome

So, poor government regulation of a product resulted in a black market for that product, and people willing to risk life and limb to supply it.

Who'd have guessed that would happen?

[GeronL]

They need to find and punish those smugglers now. lol

[mamelukesabre]

I’m not quite getting it. These tubes interlocked to do what? Build a stay-in-place form for a masonry arch?

[fella]

Smuggeling or just old fashioned small scale capitilism?

[Larry Lucido]

and turn up in many places such as Syracuse,

Dang, they beat Leif Erikson over here!

[central_va]

Vaulting Tubes explained - hot kink

[La Lydia]

Link to picture of how they were used for vaulting. Scroll down to drawing.
http://artvent-artventures.blogspot.com/2011/02/archeology-in-sicily-part-iii-earliest.html