I truly dislike the China vs. Rome debate, however, i was reading through parts of it and thought something needed to be said about logistics. The thread is closed, for good reason, so i'll post it here.
PLEASE do not rekindle the whole argument here, i just want to hear debate about the logistical issues.
-on page 2 in the old thread WarHead posted
"No, because cavalry is clearly depicted in all campaigns before of after Wudi. Xiang Yu's army at Ju Lu is said to have 30,000 made of pure cavalry, Liu Bang's xiongnu campaign is said to have 200,000 cavalry. I don't even know where you emulate your nonsense from, to the extent you've shown no source whatsoever."
1 horse/day comsumes on average 20lbs. of fodder
1 person/day consumes on average 3lbs. of millet (major grain of China)
For a cavalry force of 200,000 there would be both 200k horses, assuming no extra replacement horses, and 200k riders.
Lets assume the campaign Warhead mentioned was only a week long, though it was almost certainly longer.
Lets also assume that your average Han wooden supply wagon can carry 5 tons, about half the average capacity of todays mechanized steel farm wagons.
Using Math:
20x200,000x7=28million lbs. Fodder or 14,000 tons required
3x200,000x7=4.2million lbs. millet or 2,100 tons required
14,000+2,100=16,100 tons supply total
16,100/5=3,220 wagonfulls
Of course, Hans' wagaons were not mechanized, so horses/oxen/donkeys, etc were required for traction, in addition to a driver/attendants/guards, etc.
Lets assume every wagon had two horses, one driver, and one attendant to help load and unload.
Using More Math:
3,220x2=6,440 horses
3,220x2=6,440 men
6,440x3x7=135,240 lbs. millet or 68 tons
6,440x20x7=901,600 lbs. fodder 4,508 tons
For a total additonal tonnage of 68+4,508=4,576 tons
4,576/5=916 additonal wagonfuls, which in turn require a certain number of driver, attendants, and pack animals-though i will disregard this fact for ease of understanding.
So for a force of 200,000 cavalry involved in just a weeklong campaign, there would at the very minumum, and by using the minium calculations neccessarily be, 3,220+916=4,136 pack wagons.
Lets assume each wagon is as efficient as a modern wagon and thus is only 7 feet long. The supply train still comes out to a a whopping 7x4,136=28,952 ft. or about 5.5 miles long!
So what have we proved?
A cavalry force of 200,000 travelling through the best conditions, with no loss or attack on baggage, no need to haul any water, or any supplies other than food, for only a weeks' campaign, would at the very least have a supply train over 5.5 miles long.
However, this is not the situation describes by warhead, I beleive-and correct me if i'm wrong-that this particular army was marching west into the central asian steppe, which has been described as mostly desert, swamp, or empty plain. None of which are likely to provide sufficient water for such a host. Water weighs quite a but more than grain, and men and horses consume more water than food in any given day, so with this additional burden, i dont think it an exxageration to double the number of wagons and thus also the supply train length, which is about 10 miles long now.
Also, i think it is highly unlikely that this campign was only a week long, historically i dont really know, but lets assume it is a month, two weeks marching forward and two weeks to return. This quadruples the amount of supplies i've calculated to be neccessary, and thus the # of wagons, and thus the legnth of the supply train, which is now in excess of 40 miles long!
So, once we've considered the actual circumstances of this supposed campaign of 200k cavalry, not even including any supplies other than food and water, such as arrows for the famed han archers, horse shoes, or seige engines we must, mathmatically and unbiasedly come to the conclusion that any army with a supply train in excess of 40 miles is completly useless, and thus, would not have been used, and thus is fictional.
Sidenote: I have no doubt that there was an expedition, and am not questionaing the historial record, i just beleive that the historians, like so many others (herodotus for instance) exxagerated greatly the size of the host.