No source mentions when Dareios sent his baggage away but logic would dictate that it would be after he had decided to move north. Supporting evidence is wholly circumstantial but Curtius’ tone seems to imply that the baggage had only just arrived at Damascus; it would be incongruous to declare a town indefensible after a prolonged stay.
Damascus lies 200 miles from Sochoi so, at fifteen miles a day it would take thirteen days for the baggage to reach there. If we assume that it was the movement of Dareios’ baggage that fooled Alexander into thinking that the Persians were assaulting from the South through the Assyrian Gates then it will have moved six days before the battle. Any later and there would be no Macedonian scouts to see it, earlier is possible, but it must have been far enough away to make immediate capture impossible. Ninety miles seems about right.
Parmenion would not have set off in pursuit at once; the Thessalians having just fought a hard battle would need time to recuperate and intelligence would have to be gathered regarding the destination of the baggage.
There are two useful statements in Curtius namely that a Mardian captured with a letter of submission for Alexander was captured and escaped within a day’s ride of Damascus since his capture and escape to Damascus take place on the same day/night period, also following his flight Parmenion takes three days to intercept the column.
Parmenion was accompanied by a cavalry force of moderate size. Such forces can achieve a rate of 45 miles a day so he must have been about 135 miles from Damascus when the Mardian was captured. A single man on a horse could cover that distance in eight hours or so (an average speed of seventeen miles an hour). Since Damascus is 200 miles from Sochoi but further from Issos another day or so. Thus Parmenion would have been three days on the road when he encountered the Mardian. Allowing a day’s rest would mean that the final interception took place before the Persians reached Damascus! A delay of two days fits nicely with the story’s chronology. This also shows that Parmenion’s pursuit was at full speed and not some over cautious advance as implied by Curtius, who has him worrying about the paucity of his force.
Having found Curtius’ chronology plausible, we can further test the likelihood of his accuracy with reference to the alleged size of the baggage train and the weight of booty captured. This section is going to be heavy on numbers and maths, so be warned.
Drawing on the experience of the British Army Engel’s, ‘Logistics’, an average burden for pack animals as 250lbs and for a man as 80lbs. The animals need 10lbs of grain and 10lbs of fodder each day, water we shall assume would be accessed from local watercourses and the availability of forage would have to be considered. The men need 3lbs of grain each day and 5lbs of water, which they can be assumed to carry and replenish each day so that the weight of water carried remains 5lbs no matter how long the march (this would not be the case of desert marches).
Since only a fool sets out with the bare minimum of supplies for a march we shall assume an allowance for fifteen days rather than the thirteen a 200-mile march should take.
Over 15 days each animal would consume 150lbs of grain reducing its carrying capacity to 100lbs. It follows that they could not then take their own fodder as that would require 50lbs more than their capacity. There do not appear to have been any major settlements on the inland route taken by the baggage column but the local peasantry would have stored fodder upon which the Royal troops must have drawn. We can be sure of these peasant’s existence since Parmenion later uses them as guides.
The porters or ’gangabai’ must reserve 45lbs for their rations and 5lbs for water leaving 30lbs capacity.
7,000 animals were reported captured, so 700,000lbs capacity and 30,000 porters yield a further 900,000.
The reported booty amounts to 3,100 Talents, which translates as 176,365lbs, which this column would require 1,737 animals to carry. Further, it is clear that the force would need tents, mills and other non-comestible essentials, Curtius also mentions textiles for which no weight is given. Following Engel’s estimate of one animal per 50 men for there would be 600 fewer animals carrying rations. So we must deduct another 150,000lbs. This means that there is a residual capacity of 2,130,750lbs.
This is the possible number of additional rations, which for seven days would support 101,465 infantry.
But things are not so simple, and as soon as I find my notes I will post the even more numerically dense Part II.
