A.) Infantry and Cavalry

To begin at the beginning:

If one Prussian pace equals "nearly 29 English inches" (Duffy-P, page 120) or 4/5 yard, and one Franco-Austrian pace equals 2 feet (Nosworthy, page 204, etc.; Duffy-A, pages 284, 402, etc.) or 2/3 yard, and one infantryman-width equals 2 feet (Nosworthy, page 74; Duffy-P, page 119), while one cavalrymanwidth equals 3 feet (Nosworthy, page 137), then 200 Prussian paces equal 240 Franco-Austrian paces equal 160 yards equal 240 infantrymen shoulder-toshoulder equal 160 cavalrymen boot-to-boot.

Therefore, the same 160-yard frontage is taken up by either the 720 men in 3 ranks of an infantry battalion or the 320 horses in 2 ranks of two cavalry squadrons. Of course, numerous personnel of the battalion -- officers, sergeants, musicians, etc., amounting to perhaps 1/9 of the total thereof -- would actually be positioned behind the 3 ranks, which would tend to narrow the frontage occupied. But this is before taking into account the additional space required for the battalion guns, or for what spacing between platoons within the battalion and between one battalion and the next would exist even in a continuous or "en muraille" battle line, which taken together could easily fill to 160 yards any space left unoccupied by the battalion's infantry per se.

Accordingly, an allowance of 160 yards frontage per battalion, or 11 battalion widths per 1760-yard mile, does not seem over-generous. A close examination of the many battle maps contained in Duffy-P, Duffy-R, and elsewhere, comparing spaces occupied by the contending armies with the map scales indicated, reveals counts of [Prussian] battalions-per-mile of from 14 to 11. [Austrian and Russian battalions, still sometimes deploying in 4 ranks, could be more crowded together.]

A further sanity-check is provided by Davis, who states, "The basic tactical units were the battalion (700-800 men) which deployed on a frontage of 150-200 paces, and the platoon (70-80 men) [eight platoons per Prussian battalion] which occupied a frontage of 20-25 paces when deployed into the standard 3-rank formation."

With respect to the cavalry, Duffy (-P, page 163) states that for a 5-squadron Prussian regiment, "we should allow about 240 meters [=262.5 yards].... and therefore 49 [53.6 yards] per squadron," as opposed to the 80 yards calculated above. However, Duffy appears to be referring to deployment in the regulation 3-rank depth, as opposed to the 2-rank depth actually used in battle from 1757 (Nosworthy, page 174). Multiplying 53.6 yards by 3/2 returns us to a squadron width of 80 yards, or 1/2 battalion-width. This proportion is echoed by Cogswell (St. Paul - R&M, page 40): "The frontage of a division [=1/4 battalion or 2 platoons Prussian] of infantry thus equaled that of a half squadron of cavalry - 40 meters or 50 [sic] yards." Accordingly, we may with confidence assert a standard of 1 battalion-width = 2 squadron-widths = 160 yards.

B.) Artillery

1.) Foot Artillery

Having established frontspace - equivalents for infantry and cavalry, we turn now to artillery, by which I mean the "battery" or "position" variety, in contradistinction to the "battalion guns" organic to the infantry. The determination of a standard count of cannon per battalion-width is made problematic by the fact that, in contrast to the shoulder-to-shoulder and boot-to-boot densities characteristic of the other two arms, cannon are typically not deployed hub-to-hub, nor even with only such limited spacing as might be required for crewmen to bring ammunition around to the muzzle. Rather, enough space must be allowed for the turning-about of the horse-drawn limbers used to tow the guns around the field.

Because this turning radius would vary with the number of horses attached, which, controlling for the size and strength of the horses employed ["good and strong" for the Austrians (Duffy-A, page 280); "sheep" for the French (Kennett, page 125)], varied more or less directly with the weight of the gun being pulled [one horse per 272 pounds or so (Nosworthy, page 13)], it follows that a given frontspace would be "filled" with fewer guns the heavier, even if the lateral dimensions of the guns themselves did not much vary across the weight classes.

Further, within any given family or "system" of artillery design, this gun weight itself varied directly with its perdischarge throw-weight, as shown in the table (data from Duffy-P, page 173; Duffy-A, pages 284-285; Kennett, page 118; Osprey #304, page 39; SYWAJ Vol. VI, No. 3, page 42 and Vol. VII, No. 3, page 33), from which it follows that a given width of frontspace "filled" with like-family cannon will have always the same total, per-discharge throw-weight, regardless of the throw-weights of the individual pieces therein. 

The weight given in the leftmost column for a 3-pounder (800 pounds) is for the Hanoverian artillery, whose guns likewise appear to have been built in the old pattern.

The 3-pounders were invariably infantry weapons with the Prussians, but were used as both infantry and battery pieces by the Austrians.

Of the "Prussian Light" pieces, the 12-pounders ultimately, and the 6pounders from the outset, were assigned to the infantry.

A second model of Prussian light 24-pounder, weighing only 1470 pounds and only 12 calibers long, is better classed as a gun/howitzer hybrid, like the 10caliber "unicorns" of Russia.

Thus, Duffy [-A, page 415] quotes the complaint of an Austrian officer that 7 or 8 "miserable" 3-pounder guns "took up as much space as two good 12pounders," or, by interpolation, four good 6-pounders.

But just how many such "good 12-pounders" would fit onto the width of a battalion? We may take as a lower bound that implied by the 10-pace width of the base of the triangle said to have been formed by an Austrian piece of unspecified throw-weight, its limber, and its ammunition cart, the piece at the apex and the two vehicles each 20 paces to the rear (Duffy-A, page 278). Barring any overlap between one such triangle and the next, and assuming the piece in question to be the smallest - that is, a 3-pounder - then our battalionwidth of 240 Austrian paces could hold twenty-four such 3-pounders or just six 12-pounder-equivalents. Elsewhere Duffy (-A, page 416) quotes a contemporary observer commending the Austrian practice of concealing the location of their guns before they opened fire by putting "a platoon of infantry ... in front of every pair of pieces in the first line." Unfortunately there is specified the nationality of neither the observer nor his intended audience, and so we cannot know for sure whether by "platoon" is meant an Austrian platoon of 1/16 battalion, a Prussian platoon of 1/8 battalion, or some other standard; nor can we tell the weight of the pieces referenced.

However, I suspect that it is an Austrian-sized platoon and 3-pounder guns that are intended, which, if correct, would translate into some thirty-four 3-pounder equivalents per battalion-width [16 platoons x 2 guns, plus 2 battalion guns], or eight or nine 12-pounder equivalents.

Clauswitz, writing circa 1812, is more explicit: "A battery of eight 6pounders takes up less than one-third of the front taken up by an infantry battalion; it has less than one-eighth the men of a battalion, and yet its fire is two to three times as effective." We shall recur to the question of relative fire effectiveness later. With respect to the issue at hand, it is clear, even without knowing the relative width of a Napoleonic era to a Frederician infantry battalion [although we are required to assume that the former was yet deployed in 3 ranks], that for quantities of infantry and 6-pounder artillery of equal frontage, the number of artillery personnel would be 3/8 -- or -- fewer [say 1/3?] that of the infantry. And assuming the Napoleonic battalion to have been at least as wide as our Frederician, then Clauswitz's datum also furnishes us with an upper bound of twenty-four 6-pounders or twelve 12-pounder-equivalents per battalion-width.

If what is true regarding the personnel density relative to infantry of 6 pounder artillery is true also for other gun types -- which would require the additional but not unreasonable assumption that manning per gun varies with per-discharge throw-weight -- then, the coincidence that the complement of a battery of ten 12-pounders [=255 per Davis, including attached cavalrymen and others omitted by Duffy-P, page 171] approximates 1/3 that of our 720-man battalion, might tempt us to establish said battery, or perhaps 9/10 thereof, as our standard battalion-width artillery unit. Under the rule deduced above respecting the relation between a gun's per-discharge throw-weight and its frontspace, those nine or ten 12-pounders would occupy the same frontage as eighteen or twenty 6-pounders, which would be consistent with Clauswitz's twenty-four 6-pounders per Napoleonic-era battalion-width if our Seven Years' War battalion-width were about 3/4 or 5/6 thereof, which seems credible enough.

We are therefore confronted with a reasonable range of 8 -10, within outer bounds of 6 -12, for "Austrian" 12-pounder-equivalents per battalion-width. However, for reasons to be developed fully below under "Rate of Fire," I think it better to suppose mixed groups of heavy, medium, and, for the Austrians, even 3-pounder guns, than homogeneous 12-pounder batteries. For now I would note that Duffy's battle maps nowhere depict densities of 12-pounder guns exceeding 8 per battalion-width.

2.) Horse Artillery

The distinguishing feature of "horse" artillery as opposed to the "foot" variety discussed thus far is that the horse artillery is double-teamed for its weight (Duffy-A, page 416; Duly-P, page 180-181), producing a greater limbered marching speed but also a wider -- presumably doubled -- turning radius. From this it follows that any given frontwidth filled with horse artillery will have only half the total per-discharge throw-weight as would the same frontwidth's-worth of foot artillery of like design family.

This is not to say that horse artillery firepower was weak. As shall be seen below under "Artillery: Rate of Fire," light guns' per-minute throw-weights were significantly greater than their per-discharge throw-weights, and it was the lightest guns of which horse artillery was typically composed. Accordingly, horse artillery could generate a formidable volume of fire relative to an equalfrontwidth of the heavier foot artillery, albeit effective to a shorter range.

More Notes Relevant to the Simulation of Seven Years War Scenarios

I. Introduction
II. Tactical Unit Dimensions
III. Marching Distances Per Unit Time: Infantry and Cavalry
IV. Weapons Ranges, Rates of Fire, Endurance and Lethality

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