West Point Chemists Re-Create Medieval Gunpowder Recipes
Making powder is a bit like cooking, unless you explode more. Powder makers in the 14th and 15th centuries used black powder brought to Europe from China, after which it mixed its three ingredients one by one: saltpeter (also known as potassium nitrate), charcoal. , and sulfur. Yet they also do chef -like improvisations, including sprinkling brandy, vinegar, or varnish.
Now a group of experts at the U.S. Army Military Academy in West Point are re-creating these medieval recipes and testing the craft gunpowder on a replica cannon. They found that early gunpowder took a lot of experimentation to like-and that gave them insights into how today’s firefighters could use the same trial and error methods to assemble the explosive devices.
The project began when West Point history professor Cliff Rogers checked in Book of fireworks (German for “firework book”), a collected collection of anonymous manuscripts. Rogers says the Feuerwerkbuch is a practical handbook for master gunners, which discusses how to process ingredients for gunpowder, how to make them, and how to load and fire a cannon. Manuscripts were collected over many decades when gunpowder and artillery technology was rapidly changing; the book contains recipes from the year 1336 until its publication in 1420 and uses descriptive words such as “usually,” “better,” and “better” to describe the burning properties of each ingredient.
Rogers asked his partner Dawn Riegner, a professor of chemistry, to examine a recipe that included an unusual proportion of sulfur, saltpeter, and charcoal. “The main purpose is to examine the interpretation of a particular recipe that seems wrong,” Riegner, lead author of the team’s paper, was published this month in the journal ACS Omega. The issue turned out to be a mistranslation, not a scientific one, but it aroused their interest. “Then it happened: Well, what were all the other ingredients that middle -aged gunners put in, and what was the thought process?” According to Riegner. “Do these people without a degree in chemistry know what they are doing? Do they have an idea of what the new ingredients will do for them, or how the mix will help them? “
Riegner and Rogers decided to redo these early recipes and see if they would still work. Riegner worked in his chemistry lab with his daughter, an undergraduate engineer at the Stevens Institute of Technology, who was at home during the Covid-19 pandemic last year. “We started mixing the ingredients in the lab, starting the dry mixes,” he recalls. “And then, if necessary, as stated in the recipe, we will also add different wet solutions, whether water or varnish or vinegar.”
Once they got a final product, the mother and daughter team placed the inside of the tube containing pure oxygen to test the “bomb calorimetry” of the powder, which is a measure of the amount of heat energy that made to burn it.
Riegner said this part of the project has broken down some barriers. The ingredients used in the lab are of scientific quality, meaning they are the purest. But the sulfur and potassium nitrate used in the 14th and 15th centuries were even more polluted. That may be one reason that powder cookers are adding more ingredients – the team found that, in time, recipes began to use more sulfur to replace the more expensive saltpeter, which hard to get. Sulfur needs to be cleaned, so other additives are used, Riegner said.
It can also be used to make dry ingredients into a wet paste that is then dried and ground into powder. And there’s a third theory: Researchers believe that the alcohol in brandy may also add organic compounds to charcoal gunners and improve its combustion. But modern experimentation cannot determine whether the effects of these additives are known, because researchers are starting with higher quality ingredients. “None of them really develop motivations,” Riegner said.