The Cannon’s Breath
The Seven Years War
by Kevin Kiley, USA
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By the beginning of the Seven Years War
(1756-1763) in Europe, the Valliere artillery
system was obsolete, surpassed by both the
Prussian and Austrian artillery. [15]
In short, the French artillery performance in the Seven
Years War was dismal, and Gribeauval, having
seen and tested both the Prussian and
Austrian pieces was determined to give his
country the best possible artillery system in Europe.
Gribeauval probably started to work on
his new artillery system while still in Austria
during his tenure there. [16]
What he wanted to design was a simple system of light, accurate
field pieces that would emphasise mobility
and hitting power. He had a partner in his
endeavours, the French ambassador to Vienna,
later to become the Minister of War in
1761, the Duc de Choiseul. Choiseul was
more than interested in updating France’s obsolescent
artillery arm, and had written to the
king on the subject. Familiar with Gribeauval,
and his technical expertise in artillery because
of his service in Austria, he and Gribeauval
started to plan on implementing Gribeauval’s
ideas upon the latter’s return to France.
Gribeauval was undoubtedly chosen for the
task of revamping the French army’s artillery
by Choiseul [17]
because he had ‘a perfect knowledge in the art of Artillery’, to which
was ‘joined the most complete experience in
the alterations which had been made by the
Austrians and Prussians, since he had commanded
that of the former during several campaigns,
and had always that of the latter to oppose.’
Gribeauval wrote to Choiseul on 3 March 1762 outlining his new system, as well
as its purpose. [18] One paragraph from that correspondence is most telling in what
Gribeauval wanted to do:
However, there was one, very large,
problem facing both Choiseul and Gribeauval:
Joseph Florent de Valliere, fils, son of the
originator of the Valliere artillery system and
the current Director-General of the Artillery.
Valliere had supported Gribeauval in his technical
endeavours before leaving for Austria in
1757. It was he who had approved and accepted
for service Gribeauval’s innovative
garrison gun carriage in 1748. However, now
that he saw the work of his father threatened,
he no longer supported his protégé, but opposed
him and his entire proposal.
The debate between the two artillery systems
was long and bitter. Gribeauval officially
tested his new field guns at Strasbourg in
1764, and their performance was just as good
as the longer, older, heavier Valliere gun
tubes. The French artillery arm divided itself
into two factions: the rouges who supported
Valliere and the bleus who supported
Gribeauval. [19]
However, the successful testing
at Strasbourg, coupled with Gribeauval’s support
in the War Ministry were decisive, and
the new system was officially adopted by the
French army, replacing the older Valliere gun
tubes, on 13 August 1765. [20]
Gribeauval kept the calibre’s of the Valliere
system, 4-, 8-, and 12-pounders, for his
field artillery, but the new gun tubes were
greatly reduced by size and weight. [21]
He had all three gun tubes at 18 calibre’s length, and
they were cast at 150 pounds of metal per
pound of roundshot. In contrast, the Prussian
gun tubes were 14 calibre’s in length and had
100 pounds of metal per pound of roundshot,
and the Austrian pieces were 16 calibre’s in
length and 120 pounds of metal per pound of
roundshot. [22]
For the French pieces, this was a
great reduction in both length and weight, and
Gribeauval wanted the heavier metal to round
ratio as the guns would last longer, being able
to fire more rounds (thus extending the life of
the gun tube) compared to both the Prussian
and Austrian pieces. This would pay dividends
later once the shooting started in 1792. [23]
One of Gribeauval’s collaborators was
the Swiss gun founder, Jean Maritz, whose
family had been in French employ for decades
and who ‘dominated French cannon production’
[24] in the middle of the 18th century. The
Maritz family ran the foundries at Lyon,
Douai, and Strasbourg.
His development of the horizontal boring machine, where the gun
was rotated around a central boring mechanism
after the gun tube had been cast solid,
greatly aided the accuracy of the piece and
also placed the gun tubes to a central standard
of manufacture.
Previously each gun tube had been cast around a central core, and then bored
out with a rotating vertical bore. This led to
inaccuracy in constructing the bore along the
central axis of the gun tube. Maritz ingenious
machine solved that problem. Interestingly,
the French navy had bought the Maritz machine
before the army did. Gun tubes were
now constructed and bored with mathematical
precision to a level unheard of before this time.
After gun tubes were cast and bored, they
were both checked for faults in the metal and
‘proofed’ by test firing. If the test firing was
successful, and there were different standards
at different times for proofing the gun tubes,
they were put into service.
Testing the gun tube for casting faults was usually done in the
arsenals with a tool called a ‘cat’ or a searcher,
which was inaccurate at best. Gribeauval invented
a new ‘cat’ called the etoile mobile,
which was quite modern in appearance, and
was accurate in finding casting faults, such as
honeycombing. It was the direct ancestor of
the modern pullover gauge that is used for the
same purpose today.
Gribeauval’s reforms touched every facet
of the French artillery arm and were the most
comprehensive done in any army up to that
date, including the Lichtenstein reforms of the
Austrian artillery of the 1740s. Not only were
the gun tubes redesigned and tested, but tables
of construction were tabulated and published
for gun carriages, limbers, caissons, field forges,
and the other ancillary artillery vehicles
(which included the hacquets and pontoons
for bridging operations). [25]
Templates were
issued and sent to all of the French armouries
for standardisation of manufacture and parts
interchangeability. What was designed and
implemented was a completely integrated artillery
system which would support the new
type of warfare envisioned by the French Reformers
such as Guibert, the du Teils, de Broglie,
and Gribeauval.
Measurements for all the ancillary vehicles,
limbers, and gun carriages were painstakingly
accurate, and the tolerance for all parts
constructed for them down to 1/50th of an
inch. Although all of the technical drawings
for the new system were completed by 1767,
they were not published by Captain Jacques-Charles
Manson, who was in charge of the
manufacture and assembly of the gun carriages
and ancillary vehicles in the arsenal at
Strasbourg, until 1792-three years after
Gribeauval’s death. [26]
The Tables de construction des principauz attirails de l’artillerie proposes
ou approves depuis 1764jusque en 1789
par M. Gribeauval was originally limited to
104 copies by the king and was treated as a
classified document. Gribeauval’s papers and
designs had earlier been published by a Danish
artillery officer, Captain Henri Othon de
Scheel [27] in his two-volume Memoires
d’Artillerie, which found its way into American
service, translated by Jonathan Williams in 1800.
Gribeauval completely redesigned the
gun carriages for another reason. His gun
tubes were longer and more powerful that the
comparative Prussian and Austrian ones.
Therefore, he initially had the same problem
with recoil that Gonzales had in 1679.
Therefore he designed his gun carriages to take the
force of the recoil not only to the rear, but
retarded that so that the carriage would absorb
some of the recoil downward. This left the
guns’ recoil within acceptable parameters. [28]
Parts were interchangeable within the
‘three calibre’s’, even down to the nuts and
bolts used to put the equipment together. The
8- and 12-pounders used a Lichtenstein innovation,
two sets of trunnion plates on the carriage,
one set for the gun tube to ‘travel’ and
the other set for firing. To change the gun tube
from travelling to firing plates took no longer
that it did to unlimber the piece. [29]
Windage, the space inside the bore between
the round and the walls of the gun tube
was reduced to half the tolerance of the Lichtenstein
system, greatly improving accuracy.
This was ensured by three pieces of equipment.
For years, there was a gauge used to
measure the roundshot to ensure it would fit
inside the gun tube. This ‘go gauge’ was now
complimented with a ‘no go gauge’ which set
a lower tolerance, or limit, on the roundshot
manufactured for each of the ‘three
calibers’. [30]
Further, to ensure that there were
no casting imperfections on the outside of the
round, Gribeauval had each roundshot tested
before issue and firing by having it roll
through a metal tube, set to the tolerances of
the ‘go’ and ‘no go’ gauges, to ensure the
rounds went through cleanly.
Aiming the piece, termed ‘pointing’ during
the period, was greatly improved by the
introduction of the elevating screw, a fixed
front sight, and an adjustable rear sight that
was attached to the breech and could remain
on the gun tube while firing.
The elevating screw was attached to a wooden plate, and
when the screw was raised or lowered, the
plate elevated or depressed the gun tube. The
fixed front sight was sometimes coated with
phosphorous for night firing. These three
pieces of equipment, simple to use and manufacture,
gave French gunners an immense advantage
over their counterparts in other armies.
The Gribeauval pieces could be emplaced,
‘pointed’ and fired quicker than their
potential enemies, especially on subsequent
rounds after the company opened fire. This
added to the reduction in windage made the
Gribeauval pieces the most accurate of the
period, except perhaps for the new British
pieces that were introduced in the late eighteenth
century with a block, instead of a
bracket or split, trail and the elevating screw
attached to the cascabel knob instead of an elevating plate.
Gribeauval had each of his field pieces
(‘the three calibre’s’) constructed with accommodation
for two trail handspikes instead of
the usual one in both the Prussian and Austrian
systems. This facilitated movement of
the ‘man team’ with bricoles in that two cannoneers
manned the trail to lift if for movement.
The pieces were so well-balanced that
when the trail had to be adjusted when the
piece was pointed, however, one man would
man both handspikes to adjust the piece at the
gunner’s direction.
To facilitate the tactical movement of the
piece, Gribeauval introduced two pieces of
equipment that were simple, efficient, and
easy to use. The first, the bricole, [31]
was a length of rope attached to a leather strap worn
over the gunner’s shoulder like a crossbelt. At
the end of the rope was a metal hook. The
bricole was used to manhandle the piece, each
cannoneer attaching their hook to corresponding
hooks on the gun carriage, and they manoeuvred
their piece as a ‘man team.’
The prolonge was a length of rope 40 feet
long that was attached to the limber on one
end and the trail of the piece at the other. It
allowed the piece to be pulled by the horse
team and limber when not ‘limbered up’ and
greatly facilitated movement through rough terrain.
The ends of the gun trails were designed
to use the prolonge, and unlike any gun
carriages previously that had squared off
trails, the Gribeauval gun carriages had trails
that resembled sleds for the field pieces. When
attached to the prolonge and retiring with the
horse team and limber, the piece could still be
fired. One knowledgeable artilleryman of a
later period, Ildefonse Fave believed that if
Gribeauval had merely developed the prolonge,
he would have been ‘guaranteed’…’ a
lasting place in the history of warfare.’
Further improvements implemented by
Gribeauval were the iron axle and the screw in
vent, both of which greatly facilitated maintenance of the piece and vehicles, as well as
making them, in the case of the axle, much more sturdy on campaign.
All was not smooth sailing for Gribeauval
and his new artillery system, however.
Choiseul was replaced in 1772 as Minister of
War by Monteynard. He favoured Valliere’s
system for France, and for two years the full
implementation of the Gribeauval System was
put on hold.
Finally, the Ordinance of 3 October
1774 was published, prompted by a committee
of four French marshals who saw the
advantages of the new system over the old.
Upon Valliere fils’ death in 1776, Gribeauval
became the Inspector-General of Artillery and
the implementation of the new artillery system
was permanently realized. [32]
Initially, the Valliere pieces were retained
as siege and garrison artillery. Later, when
most of the furore had died down between
Valliere fils and Gribeauval, new siege and
fortress pieces were designed, and the implementation
of Gribeauval’s garrison carriage from 1748 was done. Work was also done on
the various calibres of mortars until the system was complete.
Howitzers had been introduced into the
French artillery in 1749. However, it was a
siege, and not a field, piece. Gribeauval introduced
the howitzer into the French field artillery,
one of 6-inches. Initially, it was modeled
on the Austrian equivalent, down to the screw
quoin, but later one of his own design replaced
it, and the elevating screw was incorporated
into the design.
The Gribeauval guns and equipment were
taken to North America in 1780 with
Rochambeau’s expeditionary force and were
employed in the siege of Yorktown in September-October 1781. Hammering the British en-trenchments
with all of the professional skill, French gunners played a decisive part, as did
Gribeauval’s new artillery system, in making
Washington a conqueror.
Gribeauval also improved the artillery’s
uniforms, changing the traditional red
breeches for dark blue to match the habit, and
modernising it. Further, organisational reforms
into companies and regiments regularised
artillery units for both administration and
combat. Although artillerymen were still
trained to serve all of the ordnance in the
French inventory, they were also assigned
guns by type to serve permanently on campaign.
A ‘division’ of six guns and two howitzers
was habitually assigned to each company
of foot artillery. This made the artillery companies
more cohesive and improved their
combat effectiveness.
Gribeauval also tackled the education
system for French artillerymen. A new curriculum
was implemented, consisting of a two-year
course emphasising theoretical knowledge and practical application. Laplace was
the new artillery examiner, and course content
consisted of mathematical drawing, optics,
tactics, geography, algebra, geometry, calculus,
mechanics, physics, chemistry, ballistics,
and ‘applied mathematics’. Mathematics was
combined with mechanical drawing, and artillery
equipment was drawn ‘exactitude and
care’ to be exact and accurate. [33]
The new artillery officers were expected to be experts
in their field, and Napoleon, an outstanding
product of one of these artillery schools, stated that
Artillery non-commissioned officers
were also now expected to ‘hit the books’ and
a school was established for them by Gribeauval.
Less emphasis was put on theoretical
learning and more on practical, but it was a
very large step in putting the artillery arm on
a more professional footing. The Ecoles des
Sergents was a success and it enhanced the
professional skill of the arm. The curriculum
consisted of mathematics, technical drawing,
practical geometry, basic physics, and
‘measuring distances with instruments’. [34]
An interesting facet of the artillery
schools is that there were no issued textbooks.
The students took detailed notes, from prepared
lectures, problems, and mechanical
drawings of the instructors, those notes being
their text as the courses progressed. A unique
way to teach and learn, one that was obviously effective.
The Cannon’s Breath Jean-Baptiste Vaquette de Gribeauval and the Development of the French Artillery Arm: 1763-1789
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