The development of smokeless powders
For about a thousand years gunpowder, or black powder (Poudre N, Poudre Noire), as it was also known, was the only practical propellant. However, there were several major tactical disadvantages in the use of black powder. Firstly, a squad of soldiers firing volleys would be completely unable to see their targets after a few shots. Secondly, their location would quickly be obvious because of the huge cloud of white smoke hanging over them. Similarly, black powder severely fouled barrels, necessitating constant cleaning, sometimes right in the middle of action. Such fouling also limited the introduction of rifled firearms, with their closer-fitting bullets. For rifles, this problem was partially overcome with the introduction of the Minie ball and the resulting rifled musket. Black powder fouling meant that early revolvers were often built with a relatively loose fit to prevent them from jamming. Further, autoloading firearms quickly become inoperable due to fouling. Black powder is also corrosive.
In 1863, Prussian artillery captain Johann F. E. Schultze patented a small arms propellent of nitrated hardwood impregnated with saltpetre or barium nitrate. Prentice received an 1866 patent for a sporting powder of nitrated paper manufactured at Stowmarket, but ballistic uniformity suffered as the paper absorbed atmospheric moisture. In 1871, Frederick Volkmann received an Austrian patent for a colloided version of Schultze powder called Collodin, which he manufactured near Vienna for use in sporting firearms. Austrian patents were not published at the time, and the Austrian Empire considered the operation a violation of the government monopoly on explosives manufacture and closed the Volkmann factory in 1875. In 1882, the Explosives Company at Stowmarket patented an improved formulation of nitrated cotton gelatinised by ether-alcohol with nitrates of potassium and barium. These propellants were suitable for shotguns but not rifles.
In 1884, a French chemist, Paul Vieille invented a form of smokeless powder, called Poudre B (Poudre Blanche = white powder). It was a great improvement over black powder. Poudre B was made from two forms of nitrocellulose (collodion and guncotton), softened with ethanol and ether, and kneaded together. It was three times more powerful than black powder and it did not generate vast quantities of smoke. Smokeless powders are smokeless because their combustion products are mainly gaseous, compared to around 60% solid products for black powder, i.e. (potassium carbonate, potassium sulfate, etc.). Poudre B was therefore immediately adopted by the French military; but it tended to become unstable over time, as the volatile solvents evaporated, and this led to many accidents. For example, two battleships, the Iéna and the Liberté blew up in Toulon harbour in 1907 and 1911, respectively.
Military adoption of ballistite
Alfred Nobel patented ballistite in 1887 whilst he was living in Paris. His formulation was composed of 10% camphor and equal parts of nitroglycerine and collodion. The camphor reacted with any acidic products of the chemical breakdown of the two explosives. This both stabilized the explosive against further decomposition and prevented spontaneous explosions. However, camphor tends to evaporate over time, leaving a potentially unstable mixture.
Nobel's patent specified that the nitrocellulose should be "of the well-known soluble kind". He offered to sell the rights of the new explosive to the French government, but they declined, largely because they had just adopted Poudre B. He subsequently licensed the rights to the Italian government, who entered into a contract, on 1 August 1889, to obtain 300,000 kilogram of ballistite; and Nobel opened a factory at Avigliana, Turin.
As Italy was a competing great power to France, this was not received well by the French press and the public. The newspapers accused Nobel of industrial espionage, by spying on Vieille, and "high treason against France". Following a police investigation he was refused permission to conduct any more research, or to manufacture explosives in France. He therefore moved to San Remo in Italy, in 1891, where he spent the last five years of his life.
Ballistite is still manufactured as a solid fuel rocket propellant, although the less volatile but chemically similar diphenylamine is used instead of camphor.
Development of Cordite and unsuccessful claim by Nobel of patent infringement
Meanwhile, a government committee in Great Britain, called the "Explosives Committee" and chaired by Sir Frederick Abel, monitored foreign developments in explosives. Abel and Sir James Dewar, who was also on the committee, jointly patented a modified form of ballistite in 1889. This consisted of 58% nitroglycerin by weight, 37% guncotton and 5% petroleum jelly. Using acetone as a solvent, it was extruded as spaghetti-like rods initially called "cord powder" or "the Committee's modification of Ballistite", but this was soon abbreviated to cordite.
After unsuccessful negotiations, in 1893 Nobel sued Abel and Dewar over patent infringement and lost the case. It then went to the Court of Appeal and the House of Lords in 1895 but he also lost the two appeals and the Nobel's Explosives Company had to pay the costs. The claim was lost because the words "of the well-known soluble kind" in his patent were taken to mean soluble collodion, and to specifically exclude the water-insoluble guncotton.
- Sharpe, Philip B. Complete Guide to Handloading 3rd Edition (1953) Funk & Wagnalls pp.141-144
- Hogg, Oliver F. G. Artillery: Its Origin, Heyday and Decline (1969) p.138-139
- Davis 1943, pp. 292–293
- Schück H. and Sohlman, R. (1929). The Life of Alfred Nobel. London: William Heinemann Ltd.
- Davis 1943, pp. 307–308
- Schűck & Sohlman 1929, p. 136
- Schűck & Sohlman 1929, pp. 140–141
- Schűck & Sohlman 1929, pp. 138–9
- Schűck & Sohlman 1929, pp. 139–140
- Schück & Sohlman, page 142
- Davis, Tenney L (1943). The Chemistry of Powder and Explosives II. New York: John Wiley & Sons, Inc.
- Schűck, H; Sohlman, R (1929). The Life of Alfred Nobel. London: William Heinemann Ltd.
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