Macedonian Soldier Stele

[Paullus Scipio]

Well, as I expected, we are going to have to agree to differ here - though it is interesting to get all this information out - one or two of the depictions you have put up are unfamiliar to me, and no doubt others! D

Ruben wrote:

However, we know that the sarissa changed in length throughout the Hellenistic period, and so it seems just as likely that the xyston could have changed in length throughout the Hellenistic period as well. Given that rigid categorizations lose their effectiveness when categories of shafted weapons were so flexible, I don't think this is the right approach.

...I'm afraid I'm going to have to take issue with this. It used to be thought that this was the case based on Theophrastus of Athens( contemporary with Philip and Alexander) says the longest 'sarissa' was "12 cubits". Polybius ( 2nd C BC, at the end of the Hellenistic age) says "14 cubits". As I posted above, with the discovery of the exact size of the 'Attic cubit', Theophrastus' 'longest sarissa' is around 19 ft/5.8 m, almost identical to Polybius' "14 cubits"( 19 ft/5.8 m) Connolly JRMES 11 2000 - which means the length of the 'sarissa' was quite consistently the same length throughout the period.
It is also consistent with medieval/renaissance Swiss and English pikes ( 18-19 ft long pikes survive in the Tower of London, and Machiavelli states Swiss pikes to be 18 ft long, though a few seem to have been slightly shorter or longer than this). It is likely then that cavalry 'sarissae'/'xysta' were also consistently much the same range of lengths. Aelian ( using late Hellenistic sources) gives this as "10 cubits, not less than 8 cubits"- 15-12 ft/ 4.4-3.7 m. We don't have a literary source for the earlier period but the detailed examples on the Alexander mosaic, and Kinch's tomb painting are consistent with this.
Both weapons were a particular size because that was their optimum, and also for practical reasons ( see previous post).

Personally, I believe that we can in a broad general sense categorise Greek and Roman shafted spear type weapons with very little overlap........javelins, purely throwing weapons, 3-4 ft/0.9-1.2m; 'longche' (gk)/'lanchea' (lat), dual purpose throwing/thrusting weapons , 5ft 6ins-6ft 6ins/1.7-2.0 m ; 'pila'/saunion/solaferum and other heavy throwing weapons, 5ft 6ins -7 ft/1.7m-2.2 m; 'Great Spear','doru'(gk) 'Hasta'(latin), thrusting weapon, 8-9ft/2.5m-2.8m; 'sarissa' two handed pike 18-20 ft/5.6m-6.2m......and for cavalry, in addition to javelins,' longche/lanchea', and 'Doru/Hasta'; the 'kamax', thrusting spear, tapering with heavy counter balance so as to be held at the rear, 8-9ft/2.5m-2.8m; 'xyston', similar but 12-15 ft /3.7-4.4m long; 'kontos', as for 'xyston' but thicker, heavier shaft requiring two-handed use for the most part.

Notice that each weapon comes in a specific, fairly limited, size range ( broadly speaking) and that there are sometimes 'gaps' between these.There are also differences in shaft thicknesses too.... As a result, I don't think that categories are terribly flexible at all - even allowing for weapon 'evolution' over time, and regional variations, and therefore categorisations of shafted weapons can be useful.

You are stating here that the cavalry carrying shields also were equipped with longchai or javelins. Now, lonche is a cognate of lancea, and refers to a light spear or a javelin - certainly not a lance.

...sorry, I wrote hastily and should have included 'Doru/Hasta' there as well....but the point remains the same - 12-15ft lances/'xysta' don't seem to be associated with shields. I tend to agree with Duncan, who went on from my earlier quote to say;

"In general, illustrations of Hellenistic cavalry with the long spear (xyston) are quite numerous, and so are illustrations of cavalry with shields; it is not likely to be co-incidence that the two are never seen together" ( AMPW p.17)

I think we may be at slight cross-purposes too, in that I get the impression that you define 'lancer' as anyone using a spear underarm...which should not be the case, since all thrusting spears - 'Doru/Hasta', 'Xyston' and even 'Kontos' can be used overhand or underarm as occasion demands ( see Sassanian rock relief of King Khusru using 'kontos' single overhand for example)

Any attempt at calculating spear lengths in this image is confounded by two facts: neither the spear of the foremost cavalryman nor that of the phalangite can be measured, since the ends are not visible. In addition to this, the length of the shaft of the rear cavalryman's spear which is visible is significantly longer than the entire length of the foremost cavalryman's.

Oh dear, I was expecting this - a difference of interpretation....see diagrams below. I believe it is possible to interpret the beltplate as either, but there are problems with both.....
With interpretation 1; the sarissa may be too long, and there is a lacuna/gap ( shown dotted) as well....but the artist could well have exaggerated the length.
With interpretation 2 ; the second cavalryman's spear (green) passes to his horse's left ( the wrong side) and disappears behind his shield, and would appear to be held horizontal the same side as the shield....though this is much the same sort of inaccuracy, due to the belt-plate's small size, as the possible lacuna in (1). Even stranger, the plane of the cavalryman's spear ( if that is what it is) EXACTLY aligns with the 'sarissa' - surely something no artist would do - but of course such a 'mistake' could well be unintentional.

Perhaps in the circumstances we ought to preclude comparative spear lengths, since it is rather ambiguous, but that still leaves the proportions of spear versus man, or horse, and I allowed for the fact that the spears 'disappear' behind bodies etc - but they don't re-appear the other side. I think my point stands even ignoring comparative spear lengths.