Henri-Joseph Paixhans

Henri-Joseph Paixhans (* January 22, 1783, Metz; † August 22, 1854, Jouy-aux-Arches) was a French artillery officer of the beginning of the 19th century.

Henri-Joseph Paixhans graduated from the École Polytechnique. He fought in the Napoleonic wars, was the representative (Député) for the Moselle department between 1830 and 1848, and became "General de Division" in 1848.

In 1823, he invented the first shell guns, which came to be called Paixhans guns (or "canons-obusiers" in the French Navy). Paixhans guns became the first naval guns to combine explosive shells and a flat trajectory, thereby triggering the demise of wooden ships, and the iron hull revolution in boat building. Paixhans also invented a "Mortier monstre" ("Monster Mortar"), using 500 kg bombs, which was used to terrible effect in the Siege of Antwerp in 1832. He was also a naval theorist claiming that a few aggressively armed small units could destroy the largest naval units of the time, making him a precursor of the French "Jeune École" school of thought.

The poet Victor Hugo wrote::"Terre! l'obus est Dieu, Paixhans est son prophète.": ("Earth! the shell is God, Paixhans is his Prophet.")

Paixhans naval guns

Explosive shells had long been in use in ground warfare (in howitzers and mortars), but they were only fired at high angles and with relatively low velocities. Shells are inherently dangerous to handle, and no solution had been found yet to combine the explosive character of the shells with the high-power and high velocity of a flat-trajectory gun.

However, before the advent of radar and modern optical controlled firing, high-trajectories were not practical for marine combat. Naval combat essentially required flat-trajectory guns in order to have some decent odds of hitting the target. Therefore naval warfare had consisted for centuries in encounters between flat-trajectory cannons using inert cannonballs, which could inflict only local damage even on wooden hulls.

Paixhans developed a delaying mechanism which, for the first time, allowed shells to be fired safely in high-powered flat-trajectory guns. The effect of explosive shells hitting wooden hulls and setting them aflame was devastating, and was demonstrated in trials against the two-decker "Pacificateur" in 1824.

The first Paixhans guns were founded in 1841. The barrel of the guns weighed about 10,000 pounds, and proved accurate to about two miles. In the 1840s, France, England, Russia and the United States had adopted the new naval guns.

The effect of the guns in an operational context was first demonstrated during the actions at Eckernförde in 1849 during the Danish-Prussian War, and especially at the Battle of Sinop in 1853 during the Crimean War.

Adoption

France

The guns were introduced on several ships in France, although they were limited to a small part of the total armamanent of each ship. The 1856 three-decker "Bretagne", the largest French warship at the time, had 36 22cm shell guns on a total of 130 cannon.

United States

The United States Navy adopted the design, and equipped several ships with 8-inch guns of 63 and 55 cwt. in 1845, and later a 10-inch shell gun of 86 cwt. Paixhans guns were used on the USS "Constitution" (4 Paixhans guns) in 1842, under the command of Foxhall A. Parker, Sr., and were also present onboard the USS "Mississippi" (10 Paixhans guns), and the USS "Susquehanna" (6 Paixhans guns) during Commodore Perry's mission to open Japan in 1853.

Russia

The Russian Navy was the first to use the guns extensively in combat. At the Battle of Sinop in 1853, Russian ships attacked and annihilated a Turkish fleet with their Paixhans explosive shell guns. The shell penetrated deep inside the wooden planking of Turkish ships, exploding and igniting the hulls.

Legacy

Ironclad warships

Wooden boats became so vulnerable that the only possible response could come with the introduction of the iron-hulled warship. The first of them was the French "La Gloire", soon followed by the HMS "Warrior".

Further developments

Paixhans's design was later improved by the American John A. Dahlgren, who wrote:

Paixhans had so far satisfied naval men of the power of shell guns as to obtain their admission on shipboard; but by unduly developing the explosive element, he had sacrificed accuracy and range.... The difference between the system of Paixhans and my own was simply that Paixhans guns were strictly shell guns, and were not designed for shot, nor for great penetration or accuracy at long ranges. They were, therefore, auxiliary to, or associates of, the shot-guns. This made a mixed armament, was objectionable as such, and never was adopted to any extent in France... My idea was, to have a gun that should generally throw shells far and accurately, with the capacity to fire solid shot when needed. Also to compose the whole battery entirely of such guns.

Floating batteries

A class of floating batteries named after Paixhans was developed by Dupuy de Lôme. Four of these ships were launched between 1861 and 1862. Originally designed for use in Cochinchina, they were built in wood and equipped with 4 ft batteries.

Writings

Paixhans wrote, among others:
* "Considérations sur l'état actuel de l'artillerie des places" (1815)
*"Nouvelle force maritime" (1822)
*"Force et faiblesse militaires de la France" (1830)
*"Constitution militaire de la France" (Paris 1849)