Saturday, May 28, 2016

The History of Saltpeter - XV

In our last couple of posts, we saw haw crude saltpeter was produced in various parts of India. In today's post, we will study the process of refinement that was undertaken there.

Crude saltpeter produced by using artificial heat sources for evaporation is generally more pure than that produced using solar energy for evaporation. This is because when artificial heat is employed, some impurities can be removed by skimming off the scum that floats to the top of the liquid when boiling it, and other impurities precipitate at the bottom of the vessel when the concentrated brine is allowed to settle and can be removed by passing the liquid through a fine cloth filter. By contrast, when the heat from the sun is used to evaporate the liquid, nearly everything that can crystallize is collected together, which includes many impurities as well.

Crude saltpeter produced by the processes detailed in our last two posts had a wide variety of purity. An analysis printed in the Agricultural Ledger of India (Volume 12) in 1905 of  55 samples of crude saltpeter from different parts of India, showed that the potassium nitrate content varied from as low as 26.8% to as high as 80%, with the average percentage predominantly at around 53%. The chief impurity in all the crude saltpeter samples was common salt (a.k.a. sodium chloride or NaCl). Some samples from Bihar showed a bit of sodium sulfate and many of the inferior samples contained quantities of dirt and other insoluble substances. Because of the impurities present in it, crude saltpeter is yellowish in color, instead of white.

A pure saltpeter sample. Click on the image to enlarge. Public domain image.

In India, the refinement of the saltpeter was generally carried out by the Mahajan community (the word 'Mahajan', while being a last name in India, is a generic title for people involved in money lending and financial services.) The Mahajans would advance money yearly to India's saltpeter men (the previously mentioned nuniahs) at 12% interest and during the hot months of April, May and June, they would be on the lookout for any crude saltpeter produced by the nuniahs and carry it off to their own factories for final refinement. If a nuniah happened to produce more crude saltpeter than what could cover his loan advance, the extra stuff would be sold off clandestinely to other petty purchasers. Since the trading networks were spread out too widely across India, to make it worth the while of Europeans with capital to attend to; it was mostly left in the hands of large Indian merchant houses, who had their small branches in every tiny village in the area and would collect the crude saltpeter, refine it and then resell it to Europeans. This trade practice was in use for hundreds of years by several generations of Mahajans, and the English were content to leave the existing system in place (as per the diary of a French adventurer, Jean-Baptiste Tavernier, some Dutch merchants unsuccessfully tried to cut into the refiners business and soon found that no one was willing to sell to them.)

An experienced person can determine fairly accurately, the amount of potassium nitrate in a crude saltpeter sample, just by looking at it, since potassium nitrate crystals are small elongated prisms, whereas common salt (sodium chloride) crystals are shaped as cubes. David Hooper, in his notes about Indian saltpeter production in 1905, mentions that he witnessed an an expert dealer, a Mahajan from Kanpur, purchasing some crude saltpeter and declaring that it was of superior quality and paying an appropriate price for it. When a sample of his purchase was later chemically analyzed, it turned out that the expert dealer was pretty accurate on his estimate of how much potassium nitrate was in it (the lab test showed 67.73%). He also mentioned that the prices of crude saltpeter tend to vary depending on the season and their cheapest price is just before the rains, because the crude saltpeter produced at this time is of inferior quality, owing to the conditions of temperatures under which it is produced. This is also the time that the refiners would buy extensively, because crude saltpeter could not be made during the rainy season.

In a saltpeter refinery, the process was similar to that carried out by the nuniahs to extract crude saltpeter, as was described a couple of posts ago. They would use nitrated earth, which was worked over and over again, with weak liquors being thrown on to it. However, after the strong liquors were collected from the filters, they were not evaporated by themselves. Instead, additional crude saltpeter crystals were dissolved into the liquid at boiling point. Potassium nitrate dissolves differently in water at different temperatures, whereas sodium chloride (the primary impurity) dissolves at a constant solubility. This means that at lower temperatures, potassium nitrate doesn't dissolve in water that much, but at higher temperatures, potassium nitrate has great solubility in water and sodium chloride has much lesser solubility. Therefore, at boiling point, the potassium nitrate dissolves into a saturated solution, whereas most of the sodium chloride crystals remain undissolved, along with other impurities (dirt, minerals etc.) that don't dissolve in water. Then, it can be filtered and allowed to settle and cool down, to deposit more purer crystals, which can then be washed in cold water to clean them (which dissolves some of the potassium nitrate, but not all, and the cold water can be recycled to extract the nitrates). The resulting crystals are about 95% pure potassium nitrate.

In our next post, we will look at a more detailed description of the refinement process, with sketches of a typical factory.

Saturday, May 21, 2016

The History of Saltpeter - XIV

In our last post, we studied how saltpeter was produced in the eastern regions of India, namely Bihar and Bengal. In today's post, we will study how it was produced in some of the other drier regions in India in the northern, central and southern parts.

Saltpeter Crystals. Click on the image to enlarge. Public domain image.

In our last post, we noted that the saltpeter production in the eastern regions of India was mainly done by a caste/tribe of people called nuniahs or luniahs, who specialized in this type of work. In the other regions of India, saltpeter production was done on a part-time basis by farmers, potters etc. These people would sell the high quality saltpeter crystals to others and keep some of the nitrated earth for themselves, to use as fertilizer for their fields. 

The following description is taken from The Agricultural Ledger, Volume 12, published in 1905, by the Office of the British Government in India, based on a report by David Hooper. The author based his description on a personal study of the saltpeter industry at Hansi, in the Hissar district of northern India, during the hot summer of 1902.

In this district, the nitrated soil is collected at Hansi fort (also known as the Asigarh fort, because of a historic sword manufacturing factory within its walls), an ancient ruin existing since about 700 AD or so, and rebuilt in the 12th century.

Views of the ruins of Asigarh fort at Hansi, India from different angles. Click on the image to enlarge.
Image licensed under the Creative Commons Attribution-Share Alike 4.0 International License by Amrahsnihcas 

A painting of Asigarh Fort and its surroundings at Hansi by Sitaram in 1815

The soil around the walls and moat of this old ruin contains nitrates and a sum of 300 per annum is paid to the Government for the privilege of collecting it. The earth is transported by donkeys, to the factory situated by the side of a main road outside of town. The arrangement of the beds for leaching the nitrous earth and evaporating the nitre liquor is shown in the following sketch:

A = Beds or filters (kurias) for the filtration of the nitrous earth.
B = Beds (patas or kiaris) for evaporating the nitre liquid.
C = Channels to conduct the liquid to the evaporating beds.
R = Jhela or reservoir.
P = Pit for storing the saltpeter
W = Well for supplying water.

The kurias (or filters, we encountered this word in our previous post) are 25 to 30 feet (7.6 - 9.1 meters) in length, 6 feet (1.8 meters) in width and 1 foot (0.3 meters) in depth. There are two of the kurias, which are sometimes sub-divided and arranged in two rows, running parallel, and situated on a broad hillock raised 3 to 4 feet (0.9 - 1.2 meters) above the ground. The beds are made of plastered clay or lime and are practically water-tight. The two evaporating beds are built on the level ground, and have concrete floors and sides. These are about 6 inches (0.15 meters) deep  and 25 to 40 feet (7.6 - 12.2 meters) square. They communicate with one another, and the smaller bed, which is raised slightly above the larger ones and is nearer the mound, serves as a reservoir for collecting any nitre water that is not required by the other beds.

The nitrated earth is carried to the kurias and is packed in them to a depth of 8 inches (0.2 meters). It is sometimes mixed with ashes in order that the soil may remain open and porous when the water is added, and possibly also with the object of decomposing the calcium and magnesium nitrate with the carbonated alkali. When the packing of the earth is complete, the water from the well (W in the figure above) is baled up by earthen pots and poured over the nitrous soil and is allowed to filter slowly through it in order to dissolve the saline matter. The saturated liquor flows off in a small stream, through the concrete channel, into the large shallow evaporating beds. Meantime, the other bed is filled as described with earth and water, and filtration and drainage go on regularly in rotation in the filters until enough liquid is obtained to fill the lower evaporating beds. The exhausted earth is removed from the kurias when the water extract has been fully drained off.

As the weather in this part of India is dry and hot during the summer, the liquid is allowed to evaporate in the shallow beds (B in the figure above), due to the heat from the sun. As the yellowish liquid in the evaporating beds becomes more concentrated, the nitre begins to crystallize at the sides and bottom, and after about seven days, most of the nitre has solidified and it is raked together into parallel ridges along the length of the bed about 3 feet (0.9 meters) apart. The mounds of crude crystals, after further drying, are collected together into heaps and then carried in baskets to a pit made in the ground a short distance away. The evaporating kurias are never allowed to become quite dry during the working season, in order to avoid cracking; as soon as the damp crystals are removed to the pits, fresh nitre liquid is run in from the reservoir, and evaporation is continued. Each kuria is said to yield 20 to 30 maunds (1645 - 2470 lbs. or 745 - 1120 kg.) of crude saltpeter per week. The nitre prepared in this manner is placed in the storage pit until it is sold. 

This method of preparing saltpeter using the heat of the sun, was practiced in the drier parts of India, where the climate permitted it. However, the crude saltpeter obtained by this method was not considered to be of as good quality as the crude saltpeter produced by artificial heat (which we studied in the previous post).

The crude saltpeter produced was then refined in a larger factory. We will study the process of this in the next couple of posts.

Saturday, May 14, 2016

The History of Saltpeter - XIII

In our last post, we saw how various European countries realized that the eastern regions of India were capable of supplying good quality saltpeter and they all fought to establish trading posts there. In today's post, we will study the process of manufacture there in some detail and also why this region produced so much high quality saltpeter.

A few weeks back, we'd studied some details about the conditions necessary for saltpeter crystals to form. We will revisit that now in some detail. The main factors needed are:

  1. Organic material: Large supply of plant and animal organic material that must be decomposed: cattle manure, plant parts, rotting wood etc.
  2. Temperature: The bacteria that perform the nitrification process become active at 54° Fahrenheit (12.22° Centigrade) and the activity increases as the temperature rises, until the temperature hits about 99° F (37.22° C), where the nitrification process reaches its maximum rate. Higher temperatures than this reduces the rate of the nitrification process. Under the right conditions, all other things being equal, 10 times as much saltpeter is obtained at 99° F, than at 54° F.
  3. Moisture: Water is necessary for the bacteria to proceed with the nitrification process. If there is drought, this will stop the nitrification process. The water holds dissolved saltpeter and other salts in the solution, and as the water evaporates in hot weather, the salt deposits on the surface of the soil.
  4. Oxygen: This is also essential for the bacteria to do their job. If the surface soil is sufficiently aerated, it allows the formation of saltpeter for a few inches of depth.
  5. Darkess: In the initial part of the saltpeter formation process, the bacteria should not be exposed to direct sunlight, in order for optimum performance.
  6. Calcium Carbonate (limestone): The presence of calcium carbonate in the soil aids the process of nitrification. 
  7. Time: The nitrification process of the bacteria takes a few months to complete, during which all the above factors should be present. 
As it happens, large parts of India were agricultural in nature, which meant availability of large amounts of wood, plants and cattle. This was particularly so in the eastern regions of Bihar and Bengal, which are plains with the Ganges river flowing through the middle of it, where most of the land was cultivated agricultural country, with a high proportion of domestic animals. These regions have the characteristics of hot summers, strong monsoon rains and presence of limestone in the soil. The farmers living in these areas were also working in conjunction with saltpeter makers for centuries and they had the whole process of manufacturing in sync with the rhythm of the seasons. Other regions in India also had many of these factors, but not as well as Bengal and Bihar. In particular, just three districts in Bihar: Tirhut, Saran and Champaran, were responsible for over two-thirds of all the saltpeter being exported from Calcutta to England annually in the nineteenth century. We have many accounts of the process written by authors such as R. W. Bingham, David Hooper, Arthur Marshall, Leather, Mukherjee and others, about how the industry worked.

In Bihar and Bengal, a special caste of people called Nuniahs or Luniahs (depending on region) were in charge of crude saltpeter production and another group called Mahajans were engaged in refined saltpeter production. In other parts of India, such as northern Punjab or the United Provinces, ordinary villagers undertook to produce saltpeter. In some other regions of India, potters would work on saltpeter production as well. The cycle went as follows:

During the rainy season, which lasts from June to October, the process of nitrification happens on the warm, moist soil, aided by the addition of organic refuse. This refuse was typically cow dung, wood and straw. Since cow dung and wood were used for fuel in rural India, villagers would collect pats of dung and straw and stick them onto the sides of huts to use later. The nuniahs would also plough special areas in the villages and spread an earth called 'sithi' on top and they had agreements with the richer villagers to let their cattle stand there for half an hour each morning and evening, so that their dung would drop on these special areas. Typically, the soil in these special areas would be so salty that ordinary crops would not grow there anyway, and the nuniahs wouldn't have to go digging about in the regular fields where agricultural crops were grown, thereby keeping everyone happy. The soil's natural supply of inorganic bases was increased by the villagers throwing fuel ashes onto the soil outside their houses and in the special areas. The villagers were paid by the nuniahs in advance, for doing this work during these months and allowing access to the specially prepared areas on their land. 

During the end of October and early November, while the rains stopped and fine weather returned, the nuniahs would visit the villages and scrape the walls of the huts and the surface of the soil of the prepared areas up to the depth of one or two inches, using ordinary spades, broken tiles or even shards from a broken pot. They would carry this nitrated soil away in baskets to be stored elsewhere. The nuniahs would return to each prepared field every four days or so (in some areas, they would come every fortnight) and repeat the process, until they had collected as much nitrated earth from the leased areas as they could before the rains returned. They would store this soil (which is rich in nitrates) in 2-4 feet high conical heaps under long sheds about 40x25 feet (or around 12x7.5 meters) where it would be protected from the weather and the precious stuff could not be washed away by the monsoon rains. The sheds would also protect the nitrated earth from direct sunlight and allow the bacteria to do their work for a few months. The amount of nitrated earth collected during this season was enough to easily keep the nuniahs and their families busy for months afterwards, doing the next stage in the process.

During the hot season months of April, May and June, the filtering and boiling process would start. The nuniahs would build earthen filtering chambers (percolators) called "kuria" or "kothi" with wet mud, which was allowed to dry. Each earthen chamber would either have circular walls about 5 to 6 feet (1.5 - 1.8 meters) in diameter or oblong walls, and a floor which slopes slightly from back to front. In the front wall is a hole at the level of the bed, under which a large earthen pot is buried, and the hole allows the nitrate liquor to drain into the pot. Above the bottom of each earthen chamber, a false bottom is laid, consisting of brushwood, bamboos and matting placed on a few loose bricks. 

A set of earthen filtering chambers (kothis) used for filtering the saltpeter. Click on the image to enlarge. Public domain image.

In the above image, you can see the man building a series of circular filtering chambers. The false bottom is clearly visible in the chamber in front. Also note the series of buried pots on the left side of the image, one in front of each filtering chamber, to collect the liquid coming out of the filters. The nitrated earth which was stored in the sheds for the previous 5-6 months would now be carefully packed into these chambers, as shown in the image above. Stones are removed from it as far as possible, and the nitrated earth is put in slightly moist and trodden down so as to leave no channels, through which water can run too rapidly or settle in. Wood ashes are generally mixed with the earth, so that the potash in them may convert into saltpeter, the nitrates of lime and magnesia. A small piece of matting is  placed on top of the nitrated earth and water is cautiously poured on top. The purpose of the matting is so that the water that is added distributes evenly. After about an hour or so, the water  passes through the filter and becomes a very strong nitrous brine solution, which trickles out of the hole in the bottom into the collecting pot. The first batch of liquid that percolates through the filter is more concentrated. More water is poured to the top of the filter after the first batch comes through, and subsequent batches of liquid are collected until the liquid trickling out of the bottom is deemed too weak to work, at which point the exhausted soil is taken out of the filter and thrown into a heap, which will be reused later (as we will see shortly). 

Meanwhile, the stronger liquid from the first few batches is transferred to a large earthenware or iron pan called a karahi, which is supported by a brick fireplace, where the liquid may be evaporated down (in other parts of India, such as Punjab, the liquid would  be transferred to shallow masonry trays, in which the concentration of the nitrates takes place through the action of the very dry air and the heat of the sun).

Evaporating the liquid in an iron pan (karahi). Click on the image to enlarge. Public domain image.

You can clearly see the shallow iron evaporating pan in the above image, placed on top of a fireplace. The pan is generally constructed from iron sheets which are riveted together. The liquid is boiled in the pan and lighter impurities, which float to the top, are skimmed off periodically. The liquid is boiled for about 7 hours until it is sufficiently concentrated. To determine this, a drop of the liquid is taken out and placed on a thumb nail. If crystals appear at once, this means the boiling process is complete. The hot boiled liquid is then transferred to open vessels made of clay and allowed to cool and the crystals that are formed are collected next morning, by filtration. The crystals are separated from the liquid and allowed to dry in the sun, but the liquid left behind is not wasted. Instead, it is combined with the next batch of liquid from the earthen filters and the solution is again boiled in the pan to get more crystals and so on. 

After several cycles of boiling, the remaining liquid becomes very saturated with salt. At this point, it is thrown on the heap of exhausted earth that was left behind by the filtration process (mentioned three paragraphs above) and left exposed to the air for a few days. This allows the exhausted earth to become nitrated once again, at which point it is filtered and boiled to extract more saltpeter and so on. The nuniahs were very careful to not lose any of the nitrates, because they often owed money that needed to be paid to the villagers and landowners for the next season. Therefore, they always strived to get the maximum yield of saltpeter possible. At the end of the hot summer season in June, the nuniahs would go back to the villages and pay the villagers an advance fee to use their lands for the next season.

The saltpeter refined by this process was somewhat crude and contained some impurities such as sodium chloride. However, it was pure enough (about 50-70% potassium nitrate) to be used for reasonable quality gunpowder, or it could be sold to other people for further refinement to produce the high-quality gunpowder.

In other parts of India, where the climate was drier (such as Punjab in northern India and parts of central and southern India), the crude saltpeter could be extracted by the heat of the sun instead of boiling artificially. We will study that process in the next post, followed by another post or two about the process used to produce refined saltpeter.

Sunday, May 8, 2016

The History of Saltpeter - XII

In our last post, we studied a few details of the regions where saltpeter could be found in India, as well as the establishment of European trading posts in India. We will study more about this, as well as the production process in India.

As we saw in our previous post, the English East India Company started importing saltpeter in a small way in the 1630s. In the early days, raw nitrated earth was being used as ballast in the East India Company ships, but the fact that it took eighteen months for a ship to make a round trip from London to India and back meant that the company needed to place orders and make payments for saltpeter well in advance of delivery, and there was not a guarantee of finding a buyer later either. However, after the English Civil War in the 1640s, it became profitable to start shipping saltpeter and in 1643, the East India Company found it profitable to refine the raw nitrated earth into saltpeter in their Indian warehouses, before shipping it out. By 1644, they established their own refinery in their trading post at Ahmedabad in India's west coast. However, the saltpeter in this region was of a rather coarse quality. Reports of high-quality saltpeter being produced around India's east coast in the Bengal region began coming in, therefore the East India Company directors sent a message to its traders in December 1650, telling them to establish a post in this area, to trade in "saltpeter, silk and sugar". The importance of saltpeter in establishing the new trading posts is evident, because the directive was to invest at least half the capital stock in saltpeter alone, and this was the only commodity for which any debt was to be allowed. With large orders of saltpeter coming in from the English government in the 1650s, the company had a guaranteed buyer and made the decision of building trading posts in India's eastern parts, with saltpeter being a major item of trade here.

By establishing trading posts in India's east coast, the English came into competition with the Portuguese, who had already established trading posts in this area since the 1530s, and the Dutch, who had also established trading posts here earlier. The regions of Bihar and Bengal were already producing saltpeter in the 1450s, well before the first European had landed in India, as mentioned in our previous post. The towns of Patna and Chapra in Bihar were two important centers of saltpeter trade (Patna is now the modern day capital of Bihar state in India, while Chapra is now much less important than before) and the East India Company set up in Patna in 1658. The person in charge of purchasing the saltpeter for them in was one Job Charnock, who later went on to set up the company headquarters in a little place called Calcutta, which later grew to become a large city and the seat of British power in India.

Around the same time, the area around Patna and Chapra had saltpeter refineries established by the Dutch, Portuguese, French and British, all vying for a bit of the business. We have the account of a French traveler, Jean-Baptiste Tavernier, from 1666, where he mentions that on a visit to Patna, "The Holland Company have a house there, by reason of their trade in saltpetre, which they refine at a great town called Choupar (Chapra). Coming to Patna, we met the Hollanders in the street, returning from Choupar, who stopped their coaches to salute us. We did not part till we had emptied two bottles of Shiras wine in the open street, which is not taken notice of in that country, where people meet with an entire freedom without any ceremony." In another section of his memoirs, he notes that "The Dutch have established a depot at Chapra; and the saltpetre being refined there, they send it by river to Hoogly. They imported boilers from Holland, and employed refiners to refine the saltpetre for themselves; but have not succeeded, because the people of the country, seeing that the Dutch wished to deprive them of the profits of refining, would not supply them any longer with whey, without the aid of which, the saltpetre cannot be bleached, for it is worth nothing at all, if it is not very white and very transparent."

We have some European accounts of the production process in India. The earliest details of the process date  from the 1620s, from a Dutch merchant named Francisco Pelsaert and an English merchant named Peter Mundy. Pelsaert was based in Agra, Northern India for 7 years, on behalf of the Dutch East India Company, while Mundy was in Surat on India's west coast in 1628. They note that the process started by collecting black earth and placing it in a shallow reservoir, which was flooded with water and the earth was trodden by workers until a paste was formed. The water was allowed to stand for two days after which it was run off into a second shallow reservoir close by, where a deposit of crude saltpeter settled. The liquid was then evaporated by boiling in iron pans, with some impurities being skimmed off the surface. The reminder was then placed in large earthen jars and left overnight, whereupon the heavier impurities sank to the bottom of the pots. The pots were then broken to free the saltpeter crystals, which were then dried in the sun.

We also know that the superintendent of the Patna factory, the above mentioned Job Charnock, was very interested in increasing the quality of saltpeter exported from India's eastern parts. As early as 1665, it was reported that the quality of saltpeter from the factory under his supervision was much improved than before:
the best that has gone from these parts, of twise boyled, occationed by the convenience of a warehouse which Mr. Charnock has built on the river side, neere our petre men, that now he viewes all they bring in, if bad, returnes it to be by them boyled over againe. Also, the whole yeare they may be bringing it by water. So that now, if [we] had monyes, 1000 tonns might easily yearly be procured.
 For his efforts, he was promoted to senior merchant in 1666 and became third in the company hierarchy for Bengal by 1676 and second in charge by 1679.

The yield of saltpeter from Bihar and Bengal was huge and by the late nineteenth century, over 20,000 tons of saltpeter were exported annually from Bihar alone. One John Stephenson observed in 1835 that practically every village in Bihar was producing saltpeter for centuries. Many of these villages were small and only produced about 5 maunds (375 lbs. or 170 kg.) per season, but since there were so many of them, the total saltpeter production added up to a huge quantity. The climatic and soil conditions in many parts of India were suitable for saltpeter production, but it was particularly so in Bihar and Bengal, where the procedures were well established in the villages for centuries. In the next post, we will study the process in detail.

Friday, April 29, 2016

The History of Saltpeter - XI

In today's post, we will look at a rather important place in the history of firearms, the region that is now the modern day country of India. What, you say? Well, the importance of India in the gunpowder trade cannot be understated, because for a few centuries, they were the source of about 80-85% of the entire world's saltpeter production. As we have seen in previous posts, no saltpeter = no gunpowder.

Back in the middle ages, the country we know today as India, was divided into several kingdoms, each with their own rulers. The knowledge of saltpeter in India seems to have been known well before the middle ages, as it is mentioned in ancient Indian texts as being used by textile makers and metallurgists. After its explosive properties were discovered in China, the technology of making fireworks came down to India around the mid-thirteenth century. As we have seen before, saltpeter can be obtained from both natural sources and artificial methods (like nitre beds). In China, most of the production of saltpeter was from nitre beds, and since the science was not fully understood, it was usually weaker than natural saltpeter. This is why China used gunpowder mainly for incendiary rockets and fireworks. In contrast, saltpeter in India was produced from mainly natural sources and was of higher quality, which enabled production of gunpowder with more ballistic strength and led to the development of rockets as well as large siege guns. Therefore, by the fifteenth century, many Indian rulers began to acquire artillery and needed saltpeter for these.

Two separate books written by court scholars from the kingdoms of Bengal and Jaunpur in Eastern India describe saltpeter production in great detail and make it clear that by 1460 AD, these two kingdoms had already developed organized saltpeter production, managed by prominent merchants who were granted monopolies by the rulers. The books describe in great detail about investment of capital, division of labor, specialists for different tasks and state control of saltpeter production. It is significant that this same region later developed into one of the top saltpeter-producing regions of India.

A map of India from the 1800s. Click on the image to enlarge. Public domain image.

The above is a map of India from the 1800s, showing various kingdoms. The areas circled in red are some of the regions that were engaged in commercial production of saltpeter and the areas circled in green are the main areas from where it was exported to the world.

We will start off by looking at the regions that produced saltpeter first (i.e. the areas marked in red). First off, we have the region in the north-eastern part, marked in the map above as Bahar and Bengal (now, the modern day states of Bihar and Bengal in India), which was one of the major areas of production of saltpeter. This is the region mentioned by the court writers above, where the kingdoms had organized saltpeter production on a commercial scale by 1460 AD. People from this area were later recruited to other kingdoms because of their knowledge and expertise in gunpowder production. In particular, the kingdom of Malwa in central India recruited many of these experts and established their own center of saltpeter production. In northern India, the area of Punjab (marked on the map as the kingdoms of Lahore and Moultan) and Delhi (marked on the map as Delhi and Agra) were both centers of saltpeter production. In Punjab, the main centers were Lahore and Multan (marked as Moultan on the map) and in the Delhi area, the main centers were Agra and Hissar.

Down in the southern part of India, the regions around the modern day states of Karnataka, Tamil Nadu and Telengana (seen in the map as Carnatic, Golconda and Mysore) were known for saltpeter production, in particular, the towns of Coimbatore, Anantapur, Kurnool and Guntur (the first two towns are marked on the map).

Meanwhile, over in Europe, during the fifteenth century, the Age of Exploration had started and the pioneers behind it were the kingdoms of Portugal and Spain (Spain was then divided into the kingdoms of Castile and Aragon). Before then, from the 8th to the 15th century, the various Italian kingdoms, such as the Republic of Venice, Genoa, Pisa etc. had a monopoly on trade between Europe and Asia, via the Arabs. In the early part of the 15th century, Prince Henry the Navigator of Portugal decided to explore the west coast of Africa. Development of new types of ships (carracks and caravels) made it possible to sail into the open Atlantic ocean, which was much rougher than the calm waters of the Mediterranean sea. Due to travelers like Marco Polo and Pedro da Covilha, accounts of the riches of China and India became known to Europeans, but the land routes passed through several countries, each with their own difficulties and dangers for travelers. Prince Henry the Navigator had already explored enough of the African coast beyond the Sahara desert that he could bypass the Arab and Berber traders and trade with the African kingdoms directly. The next prize was to establish a sea-route to the fabled country of India, and both the Portuguese and the Spaniards were trying to discover how to do it, so that they could bypass all the countries in between and trade with India directly. The Portuguese concentrated on finding a route by sailing south around the tip of Africa and then sailing north and eastwards towards what they hoped was India. Meanwhile, a navigator from the Italian republic of Genoa, named Christopher Columbus, hoped to find a westward route to India and sailed in that direction, on behalf of Spain in 1492 AD. We all know what Christopher Columbus accidentally discovered instead :-). When he got back to Europe, a minor squabble started between Spain and Portugal, which was settled by Pope Alexander VI in 1494 with the Treaty of Tordesillas, which stated that all lands west of a meridian past Cape Verde islands could be claimed by Spain and all lands east of this line could be claimed by Portugal (of course, the opinion of the people already living on these lands wasn't considered!). The Portuguese liked this deal because this gave them claim to Africa, Asia and part of South America (Brazil), whereas the Spanish were given control of mostly unknown territory. Of course, the other non-catholic kingdoms in Europe, such as England, Holland, Denmark etc., paid little attention to the Pope's orders and got into the exploration game afterwards. Meanwhile, in 1498, a Portuguese expedition under Admiral Vasco da Gama, successfully rounded the coast of Africa and reached the fabled land of India, landing at the town of Calicut (circled in green in the south-western coast of India). The discovery of a viable sea route led to yearly fleets of ships leaving from Portugal to India and the Portuguese soon established trading posts in the southern coast of India, at Cochin, Goa, Calicut, San Thome (now a suburb of Madras city) and Pulicat and the town of Chittagong (now in Bangladesh) on India's eastern coast. Initially, the Portuguese only traded in cotton, spices, pepper etc. and saltpeter purchases were only made by soldiers buying their own supplies from dealers. However, by 1510, the Portuguese had established a powder mill in Goa (marked in green on the map, towards the west coast of India) and were exporting gunpowder and saltpeter from Goa and Surat, back to Portugal. Soon after, they also established trading treaties with kingdoms on India's south-eastern coast and were also exporting from San Thome (a suburb of Madras city, circled in the map in green) and Pulicat (also marked on the map) and the volume of trade increased as the years went by. There is a letter from 1605, from the King of Spain to the Portuguese viceroy of Goa (on the south-west coast of India), directing him to send an order of 12 casks of saltpeter.

Soon enough, other European kingdoms saw how rich the Portuguese were getting from their Asian imports and decided that they needed to set up trading posts in Asia too. Despite the Pope's orders that only Spain and Portugal were authorized to claim lands around the world, the mainly non-catholic countries, such as England. the Netherlands, Denmark and France openly defied his orders and decided to develop their own businesses.

The first was the English East India Company (EIC), also called the Honorable East India Company, formed on 31st December 1600 and the first ship left England in 1601 (Fans of the Pirates of the Caribbean movie series might have seen this company mentioned more than a few times in the movies, but it is not a fictional company, it actually existed and grew to become the largest company in the world, at one point, controlling over 50% of the world's trade by itself). In 1602, the Dutch established their Dutch East India company (VOC - Vereenigde Oost-Indische Compagnie), which was the world's first multinational corporation and the first company in the world to issue stock. These two companies started establishing bases all over Asia. In India, the Dutch captured the trading post of Pulicat from the Portuguese in 1609, while the English East India Company established trading posts in Surat (1619), Madras (1639), Bombay (1668, acquired by England from the Portuguese as part of the dowry of Catherine de Braganza, when she married King Charles II) and Calcutta (established 1690).

The Dutch VOC company started exporting saltpeter from India (from Pulicat town) as ship ballast in 1617 and the English learned this from them and started doing so in 1627. Correspondence between East India Company Headquarters in London and their trading outposts in India are quite revealing on the growth of the saltpeter trade. For instance, in December 1630, two ships, the Discovery and the Reformation, traveling from Surat to London, carried 597 bales of saltpeter instead of rocks for ballast, along with their regular cargo of pepper, cotton, indigo, calico cloth etc. In 1638, the Company asked captains to prefer loading sugar, preserved ginger, cinnamon etc. on the grounds that 'saltpeter is ... troublesome to bring home, as it infects and spoils other goods.' The agents in Surat responded that while saltpeter was certainly 'a bad neighbor to better goods', a sprinkling of pepper 'praeventeth all praejudice'. A letter to the Company headquarters in 1639 even suggests to not import as much saltpeter on the ship, so as to keep the demand up and 'increase its value in England'. By 1643, with the English Civil War in full swing, English saltpeter men and European sources could not meet the demand for saltpeter and the East India Company started refining their own saltpeter in Surat and Ahmedabad, before shipping it out. The English began to receive reports of the availability of high quality saltpeter available from the north-east region of India, in Bengal and Bihar. However, the Portuguese were already established in that area since the 1530s (in Chittagong) and so were the Dutch. Soon after, the English started to concentrate their efforts in Bengal as well, later edging out both the Portuguese and Dutch from this area (we will study how that happened in our next post).

Seeing the success of the Portuguese, Dutch and English companies, other European countries also tried to get in to the action and established their own (often short-lived) East India Companies. The Danes founded the Danish East India Company in 1616 and built Fort Danesborg in Tranquebar, south of Madras (marked in green in the map), the Prussians established the Prussian East India Company (1752), the Swedish had the Swedish East India Company (1731) and the French formed the French East India Company (1664). The French were slightly more successful than the others in the beginning, until the English seized control over most of India and pushed them out. Nevertheless, the French still kept trading posts in Pondicherry (south-east India) and Chandernagore (eastern India near Calcutta) until the 1950s, but they couldn't get much saltpeter out of India, because of English interference.

In the next post, we will look at how the English managed to edge out all the other competitors and gain a monopoly on Indian saltpeter production. We will also examine how saltpeter was produced in India in some detail.

Wednesday, April 27, 2016

The History of Saltpeter - X

In our last post, we looked at how saltpeter was obtained in England during the reign of Queen Elizabeth I. During her reign, England built up their stocks of saltpeter and gunpowder, and her successor, King James I, didn't need that much. Incidentally, this is the same ruler that authorized an official translation of the Bible into English, that we know today as the King James Version of the Bible.

James I of England. Click on the image to enlarge.

During the early part of his reign, he attempted to curb the excesses of the saltpeter men and reduce their powers. However, in 1618, the Thirty Years War started in continental Europe, and the need for saltpeter extraction came back into focus, and the saltpeter men were back in business. However, one more significant development started during the reign of King James I. His predecessor, Queen Elizabeth, issued a royal charter authorizing the creation of the Honourable East India Company on December 31st, 1600 AD. Initially authorized to trade in cotton, spices, silk, indigo etc., the company also began to import small quantities of Indian saltpeter during James's reign. By the time of the reign of King Charles I, the imports of Indian saltpeter were still small and England was deriving most of its supplies from local saltpeter men or importing from Europe. During King Charles I's reign, England was obtaining about 280 tons of saltpeter a year in the 1630s, but when the English Civil War broke out in the 1640s, the demand for saltpeter rose again and the English saltpeter men and other European producers could not meet their needs. The East India Company saw an opportunity and stepped up the quantity of their saltpeter imports from India. By the time of the Restoration in the 1660s, when King Charles II became the king of England, the East India Company were shipping over 1000 tons of saltpeter annually from India and the need for saltpeter men in England went away soon afterwards, giving the East India Company a virtual monopoly.

The East India Company found the trade in saltpeter very profitable for them. While they imported other goods to England, the mark-up on cotton textiles was seldom more than 200%, whereas they could easily mark-up saltpeter to well over 400% and still find willing buyers. Not only that, since saltpeter is a chemical, it isn't a perishable item unlike their other imports (tea, pepper, spices, indigo etc.) and can withstand rough handling. They used it as ballast on their ships and simply emptied their holds upon returning to England. Saltpeter also repels insects and bacteria, so it also helped preserve the hulls of their wooden ships.

It might be interesting to note that by the time the East India Company (and other European countries) first started trading in India around 1600 AD, saltpeter manufacturing was already a well-established industry in different parts of India for at least 150 years or so and they were the largest manufacturers of saltpeter in the world until the importance of black powder began to decline in the late 1800s. The saltpeter produced in India was not only of better quality, it was also cheaper than anywhere else in the world and was produced in huge quantities as well. The British held a monopoly on Indian saltpeter and were very happy to supply their allies (Sweden, Portugal, Spain etc.) with it, but kept it out of the hands of their enemies. This is why the French were forced to develop saltpeter plantations, because they couldn't access Indian saltpeter the way that the British could. By the time of the battle of Waterloo in 1815, the East India company had exported 7300 tons of saltpeter that year alone. During the US Civil War, both the North and the South were supplied with Indian saltpeter from England. The following quote is by C. H. Davis of the Bureau of Ordnance, US Navy from November 22nd, 1862 in a report to the US Congress:
I feel it, therefore, to be my first duty to urge that suitable provision of ordnance material be made for probable future necessities of the Navy. Most important among them is nitre, which enters so largely into the composition of gunpowder that it may be said to be gunpowder itself, with some slight additions of sulphur and charcoal under proper combination.
It is not produced naturally in this country, nor by any other but India, except in insignificant quantities.
Hindostan (India) alone supplies the whole world, which being a British dependency, places us entirely at the mercy or caprice of that power for our stock of this essential article.
Therefore, a study of the history of saltpeter production in India will be the subject of the next few posts in this series.

Tuesday, April 26, 2016

The History of Saltpeter - IX

In our previous post, we looked into some early history of saltpeter and gunpowder in England, until the reign of Henry VIII. We will now study some further developments under his daughter, Queen Elizabeth I.

Queen Elizabeth I of England. Click on the image to enlarge. Public domain image.

Elizabeth was the daughter of King Henry VIII, but she was not the immediate ruler after his death in 1547. Instead, Edward VI, her half-brother, became king for a few years (1547-1553), followed by his cousin, Lady Jane Grey (only 19 days in July 1553) and then, her half-sister, Queen Mary I (1553-1558). After Elizabeth deposed her half-sister Mary and became Queen Elizabeth I in 1558, her new secretary of state was Sir William Cecil, who had also served in the same role earlier for her half-brother Edward VI in 1550. This is the same William Cecil who was mentioned in our last post, who later became Baron Burghley.

At this time, England was still mostly importing saltpeter and gunpowder from other places in Europe, and during the first few weeks of Elizabeth's reign, the amounts of saltpeter and gunpowder available in England were greatly reduced. Fearing that other powerful European rulers (such as the French king, the Spanish king, the Portuguese king, the Hapsburg dynasty etc.) could attempt to invade England soon, William Cecil started working with Elizabeth's Council of ministers to build up England's stocks of gunpowder and saltpeter on an urgent basis.

To do this, they went to dealers of saltpeter in Europe. The problem was that the same people who sold saltpeter to the British, were also selling it to the other European rulers (the French king, the Spanish king, the Hapsburgs etc.) as well. Therefore, William Cecil advertised that England was willing to pay higher prices for saltpeter and gunpowder than anyone else, and was perfectly happy to encourage smugglers to supply them. Of course, there was the danger of the supplies being intercepted by the other countries, so he contacted as many dealers as possible, to ensure that there would be multiple sources. Pretty soon, Italian, Flemish, Dutch and English merchants were all supplying England. Cecil sent his agent, Sir Thomas Gresham, to Flanders, Germany and Netherlands, to talk to dealers in those regions and buy everything that they had. By 1660, Sir Thomas Gresham had obtained over 200 tons of saltpeter, enough to take care of England's needs for at least two years, but the quest for more saltpeter did not end there. Gresham's people went to Hungary, Bohemia, Russia and Denmark to get more supplies. England even traded as far south as Morocco and the Persian empire, exchanging timber and iron cannon balls for saltpeter. Of course, much of this had to happen in secret, so that the other rulers would not know how much gunpowder England had. Sir Thomas Gresham prophetically wrote to the Queen in 1563, that '£20,000 of saltpeter would be more useful to her than £100,000 in gold'.

At the same time, England also tried to jumpstart their own local production of saltpeter, reasoning that this would reduce their reliance on foreign suppliers and hostile countries stopping ships from reaching England. They also argued that local manufacturing would be cheaper and of better quality, as well as creating local jobs. William Cecil was already aware, through his agents, that some German states had developed techniques to produce saltpeter plantations, and he sought to import this knowledge to England. At the same time he was setting up to import supplies from an Italian merchant in 1561, he also found a German engineer, Gerard Honrick (or Hoenrich), who was willing to transfer the technology for £300. Honrick talked about his method of mixing earth with urine, horse dung and lime and then refining and crystallizing it to produce saltpeter. We already discussed his methods some time earlier, so we will not repeat those details here again.  Honrick envisioned a system where vast nitre beds would be set up to supply centrally located factories to refine and extract saltpeter. However, two months later, he was complaining that England hadn't paid him for his transfer of knowledge.

Instead, the British government granted an exclusive 10 year license to a pair of British merchants, Cockeram and Barnes, to supply them with saltpeter from England. As part of the license, they were granted the power to dig anywhere they like. Of course, instead of working on any sort of saltpeter plantation technology, Cockeram and Barnes were quite content to dig in other people's lands, just like the saltpeter men of old. While there were many attempts made to develop saltpeter plantations, the majority of England's supply simply came from saltpeter men searching around England and digging up other people's property. Other experts, such as Leonard Engelbreght of Aachen and the Flemish merchant, Cornelius Stephinson, attempted to set up saltpeter beds in England at different times, but most of these efforts proved unsuccessful. Instead, England became more reliant on saltpeter men searching through various places in England to find natural supplies and licenses to dig were granted to more people. It is interesting to note that when the Spanish Armada tried to invade England in 1588, the British ships never had a shortage of gunpowder during the sea battle. By the end of Queen Elizabeth's reign, about 50% of England's saltpeter supply was from domestic sources, largely using a network of saltpeter men throughout the country. While these saltpeter men were hated by the average citizens, their complaints were ignored, on the grounds of national security. It was left to Queen Elizabeth's successors to figure out how to obtain saltpeter without angering the citizens. We will study how they managed to do this in the next post, when we study the rise of the British East India Company.