Could the Persian Empire logistically support an army several million strong?

[Justin Swanton]

could wine amphorae be reused for grain and vice versa (assuming the theory holds water....or grain)?

I suppose so.

[Erpingham]

could wine amphorae be reused for grain and vice versa (assuming the theory holds water....or grain)?

Not really.  The neck is too narrow to easily fill with grain.  Herodotus, I believe, said they were reused for shipping water though.

[Imperial Dave]

grain does behave like a fluid so it is possible although maybe unlikely here. Reuse of amphorae for whatever is a nice aside discussion though

[Flaminpig0]

I seem to remember calculating that the amount of grain that was apparently needed for the 6 million host would need 88 million amphorae

[Erpingham]

Reuse of amphorae for whatever is a nice aside discussion though

Perhaps a bit too marginal on the military history even for us?  I must admit, Justin has had me looking at more articles on amphorae since my archaeology days.  I get the impression that to really get to grips with amphora studies, you need an anorak.

[Jim Webster]

I seem to remember calculating that the amount of grain that was apparently needed for the 6 million host would need 88 million amphorae

That's too much. A typical amphora used for transporting wine can hold about 40 litres. Grain weighs 0.79g per cm³ so the amphora can hold 31.6 kg of wheat.

you  forget that the weight of the amphora is the weight of its load, so your 31kg amphora will weigh 62kg. If you're unloading these by hand from open boats onto a beach, I'd rather handle 60lb amphorae than 60kg ones

Or alternatively you could do what everybody did and carry it in sacks where you have very little added weight

Which saves having to set up a previously unexpected amphorae industry.
I suppose if somebody is going to transport unfeasibly large amounts of grain to feed an impossibly large army then they're going to have to create strange new industries on the strength of it 

The whole discussion merely convinces me that the answer to the question is 'No'

[Imperial Dave]

I seem to remember calculating that the amount of grain that was apparently needed for the 6 million host would need 88 million amphorae

[Jim Webster]

grain does behave like a fluid so it is possible although maybe unlikely here. Reuse of amphorae for whatever is a nice aside discussion though

it does behave like a fluid but can 'bridge' . But any neck that's wide enough to fill with a shovel is not going to bridge when you empty it 

[Erpingham]

We seem to have an attack of the giant images.

Contributors may not realise that you can use the image width parameter to control the size of the image in a post

Set the first image parameter in the sq bracket to [img width=x] where x is the size.  I find that 300 is good.  Make sure you have no space in front or after the = sign. Leave the closing bracket as is.

But maybe giant images are "in" at the moment, in which case, ignore the above

[Erpingham]

Specially for Dave, who is fascinated by amphorae, here is another article on amphorae as shipping containers (as opposed to things to create typologies of).   

[Justin Swanton]

Just a comparator for amphora production: Rome needed at least 7500 000 litres of olive oil each year which translates to 187500 amphorae per annum, all just used once.

Another estimate puts it at 20 000 000 litres of olive oil (500 000 amphorae) and, conservatively, 100,000,000 litres of wine (4,000,000 amphorae). That's just Rome for just one year. What was stopping Persia from matching these production figures for amphorae?

And where are the wine shards?

[Jim Webster]

Just a comparator for amphora production: Rome needed at least 7500 000 litres of olive oil each year which translates to 187500 amphorae per annum, all just used once.

Another estimate puts it at 20 000 000 litres of olive oil (500 000 amphorae) and, conservatively, 100,000,000 litres of wine (4,000,000 amphorae). That's just Rome for just one year. What was stopping Persia from matching these production figures for amphorae?

It's not that the Persians couldn't produce amphorae.
It's just that to transport six million men to Greece they've got to find a minimum of 300,000 labourers in Egypt, expand their amphorae production industry several fold, but only for four years when it can dwindle back to normal, somehow find extra shipping and ships and men to load and unload them, and this is as well as taking 6 million men out of the workforce. (Given an estimated population of the Empire of 50 million, assuming half to be male and perhaps two thirds of them to be of 'working age' (rather than military age) there are perhaps 17 million men available. You're pulling 6 million of them out  of the economy for over a year. (That assumes that they had to set off marching to Sardis to overwinter in the year before the campaign.
On top of this we have an untold number of 'engineers' and labourers to prepare roads and make canals.

Sorry, but I cannot see it being done.

[Imperial Dave]

Specially for Dave, who is fascinated by amphorae, here is another article on amphorae as shipping containers (as opposed to things to create typologies of).

actually quite enjoyed that article

should I get my anorak now or later 

[Imperial Dave]

grain does behave like a fluid so it is possible although maybe unlikely here. Reuse of amphorae for whatever is a nice aside discussion though

it does behave like a fluid but can 'bridge' . But any neck that's wide enough to fill with a shovel is not going to bridge when you empty it 

yes it can bridge. I've seen it a few times in my working life (being a brewer) and I acknowledge its unlikely for amphorae usage. Still an interesting topic though

[Patrick Waterson]

It is an understandable intellectual approach - there is nothing morally reprehensible about expressing an outlook based on one's own culture - but it is not legitimate for understanding other cultures at different periods in history.

But alas its all we have   It is probably a philosophical difference in approach to the past between us.  You believe that the historian can completely discard their own culture in looking at the past and I don't.  Where we agree, I think, is that we must endeavour to recognise our cultural biases and seek to minimise their impact.

That at least we can agree upon.  If one is able to leave aside one's own culture, or at least its outlook and assumptions, it does permit a better understanding of other cultures and suspends the knee-jerk negativity reflex when the apparently unlikely is encountered.