Tuesday, January 17, 2017

Smokeless Powders: Further Developments by Abel and Schultze

In our last post, we studied some discoveries by Baron Von Lenk, who succeeded in developing a process to manufacture gun cotton in larger quantities. The Austrian empire adopted his gun cotton as a propellant to replace black powder and supplied thirty howitzer batteries with gun cotton cartridges, as well as a new model of the Lorenz rifle (the M1862 model) to use gun cotton. Two factories in Austria started to manufacture gun cotton based on his process.

The gun cotton, as made by Von Lenk's process, retained the fibrous nature of the original cotton. The Austrians spun it into threads and braided them together, or wound them on wooden or paper bobbins, and arranged them in cartridges, so as to secure the desired air gaps in between and insure proper ignition. The Austrians found that this propellant was not affected by dampness, only required a charge of 1/4th to 1/3rd of the amount of black powder previously used, left less residue inside the barrel, produced less smoke and the gases evolved were also less harmful to the weapons and the men around them. France and England got interested in his discoveries and sent scientists to study the Austrian process as much as they were willing to reveal and Von Lenk also lent his expertise to scientists from both countries.

Unfortunately, there was an accident in 1862 in the factory at Hirtenberg, Austria, which blew up for some unknown reason. Soon after this, a British company called Thomas Prentice & Co. started to manufacture gun cotton in 1863, in a town called Stowmarket in England. Shortly thereafter, Sir Frederick Abel also began to research producing nitrocellulose safely at the Royal Gunpowder Mills at Waltham Abbey, England. His process was based on Von Lenk's process as described in our previous post, but he effected a more complete purification of the gun cotton by pulping it before the final washing process, thereby cutting the tubular fibers into short lengths and rendering it possible to remove the last traces of acid retained within the tubes by capillary action. Traces of acid remaining in the gun cotton was what caused it to decompose over time. He patented this method in 1865, just around the time that the second Austrian factory also blew up. The Austrians had also had some accidents with their guns and after the second factory blew up, they decided to stop using gun cotton in their military. Meanwhile, Abel continued to experiment in England with his pulped, purified gun cotton, which he could compress into various shapes and in 1867 and 1868, he got some very promising results when used with field artillery. However, the British military were still very wary of gun cotton and military authorities were concerned about safety issues more than the advantages of the smokeless powder technologies. Also, the Thomas Prentice & Co. factory in Stowmarket blew up in 1871 and this was another reason why the British military discontinued further research for artillery and small arms for about twenty years. Instead, the compressed gun cotton was used in naval mines and for filling torpedoes and this is where the entire gun cotton production at the Waltham Abbey factories went to for the next couple of decades.

While military interest in gun cotton had decreased, civilians were very interested in this new technology. In particular, sportsmen who liked to hunt, appreciated the lack of smoke combined with higher velocities and lack of fouling and the next few years of developments were largely done in response to their demands. Naturally, the goal was to reduce the force of the explosion, so that barrels would not rupture, as had happened in the previous years. Around 1863, a Prussian artillery officer, Captain Johann Edward Schultze, invented a powder made from well purified and partially nitrated wood. His process started by sawing the wood into thin sheets about 1/16th of an inch in thickness, which was then passed through a machine that punched out disks or grains of uniform size. The next step was to remove the resinous matter from the disks, which was done by boiling the disks in sodium carbonate solution, washing them, steaming them, bleaching them with chloride of lime and then drying them. After this, the cellulose was nitrated in an acid mixture similar to the Von Lenk process. After this, the nitrated wood was then steeped in a solution of potassium nitrate and barium nitrate and then dried, which completed the process of manufacturing process. Using this process, the nitrocellulose that was produced was diluted with unconverted cellulose and metallic nitrates, which allowed for an even rate of combustion.

The advantage of using nitrates and organic substances as diluents was soon copied by other people and many other powders were soon on the market, using potassium, sodium and barium nitrates, and potassium nitrate (saltpeter), while sugar, cellulose, charcoal, sulfur, starch, gums, resins and paraffin were all used as combustible diluents and cementing agents.

Schultze started manufacturing his smokeless powder in a factory in Potsdam, near Berlin, around 1864. His powder soon gained popularity among civilian hunters. However, in 1868, there was a major fire in his factory and it burned to the ground. Shortly after this event, over in England, near a town called Fritham in the New Forest area, at a site called Eyeworth Lodge, a new factory called the Schultze Gunpowder Factory was established by two businessmen, Clement Dale and William Bailey. There was already an earlier attempt about 7 years previously to establish a black powder factory at the same site, which was not successful. The new owners hoped to capitalize on smokeless powder technology as well as the name of Captain Schultze, from whom they obtained a license to manufacture the powder. It must be noted that while Captain Schultze was not really directly involved with the new Schultze Gunpowder Factory, they did use his original manufacturing process and subsequently improved it over the years as well.

Click on the image to enlarge.

Initially, the factory was not very successful and in 1871, they only had four employees. The November 1872 edition of Popular Science had this to say about the factory and its production process:

"Here and there at intervals wide apart are various buildings of light structure from one of which rises a tall chimney instrumental in raising steam to drive a 10HP sawing machine which rapidly creates the "wood powder". This is subjected to chemical washing leaving hardly anything behind save pure woody material, known as lignine or cellulose. The next operation involves the conversion of these cellulose grains into a sort of gun cotton material by digestion with a mixture of sulphuric and nitric acids. Next it is washed with carbonate of soda and dried. The resultant grains are stored away until the time of packaging and dispatch when they are charged with a definite percentage of a nitrate powder -- nitrate of baryta is preferred.  All the buildings requisite for manufacturing this explosive are cheap and flimsy so that if they did catch fire no loss would ensue. The plant and machinery is of small cost in comparison to that used for making black gunpowder and Schultze wood powder is sold at a price commensurate with its cheap production."

In 1874, a talented self-taught chemist named R.W.S. Griffiths was appointed as the general manager and he refined the production process. Soon after this, the company began to become famous for the quality of its powder, particularly after samples of powder were successfully tried out in a series of trials organized by The Field magazine. By 1878, it became a leader in the world's sporting powder market. Many of the famous cartridge manufacturers, such as Eley Brothers, Kynoch and Union Metallic Cartridge Co. (UMC), used Schultze powder in their cartridges. The company rapidly expanded and the population of the local village of Fritham expanded with it, causing a reservoir, a new church, a store and workers houses to be built. Nevertheless, powder manufacturing remained a dangerous process and therefore, the wages for workers at that factory were around double that of those working in agriculture at that time.

At its peak, the Schultze Gunpowder Factory also opened offices in Gresham Street, London and had agents in various cities around the world. They became the largest manufacturer of smokeless powder for sporting use and produced about 75% of the world's supply. In 1897, they formed an American branch in conjunction with E.C. Gunpowder Co. and called it American E.C. & Schultze Gunpowder.

One of the most famous users of Schultze powders was the legendary American exhibition shooter, Annie Oakley, who was the star of Buffalo Bill's Wild West Show.

The legendary Annie Oakley. Click on the image to enlarge. Public domain image.

Annie Oakley had mentioned in several interviews, that she only used Schultze powder for her performances. Interestingly, when the Wild West Show toured France in 1889, she brought along fifty pounds of Schultze powder with her and then discovered at the dock that there was a French law that forbade the import of foreign gunpowders! At that time, the quality of French powders was not as good, because of a government monopoly on powder manufacturing and she didn't have the time to experiment with a new brand anyway. Fearing that her accuracy would be affected, there was only one thing she could do: smuggle the powder in! She obtained five hot-water bottles and enlisted four other lady riders with the show as co-conspirators. They filled the hot-water bottles with Schultze powder and each woman wore a dress with a bustle, hiding the bottles within. In fact, Annie had never worn a bustle in her life before that day, but she admitted that on this occasion she was glad to do so. She led the women safely through the customs line and into France. As she later admitted, "We sure did attract some attention when we went down the gang plank, for although the bustle originated in France, it was going out of fashion at that time". Even then, as the tour went on in France, her supply of powder eventually ran out and her shooting accuracy was affected because she had to use French powder. In fact, the French powder exploded one of her best guns and gave her a big bruise and her husband noted that no matter how carefully one loaded French powder into cartridges, no two ever fired alike. Luckily for her, in Marseilles, she received a notice to go to the Customs House to pick up a box mailed to her by some friends in England. The box was rather large and inside it were two dozen fresh eggs and an unsigned note telling her that she should try the packing material out in her gun before throwing it away. The eggs were packed in Schultze powder! She gladly paid the 40 cent import duty on the eggs and as she reported, "I never shot better in my life than I did the next three days, either winning or dividing every event. It may be that I was in better form, but I'm sure my Schultze load had a great deal to do with my good scores."

By the early 1900s, Schultze Gunpowder Company expanded so much that they had to move to Redbridge in Southampton, which was more suitable for transportation of its products. However, the company really suffered during the World War I period due to anti-German sentiment. In fact, the company had to take out newspaper advertisements declaring that despite their German-sounding name, all the owners, management and workers were British! Soon afterwards, a bunch of British powder manufacturers all combined together to form Nobel Industries, which later combined with three other companies in 1920 to form ICI (Imperial Chemical Industries),which was Britain's largest manufacturer for most of its history. This was around the time that the Schultze factory at Eyeworth Lodge was closed. All that remains there today are a few buildings and a farm.

In our next post, we will how gun cotton started to attract the interest of militaries once again.

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