History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c37: Chemistry In Practical Arts (Ii)

History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c37

Language: English

c37.s1 Gunpowder, Saltpetre, The Mineral Acids, Alum, Etc. — 26 parts
c37.s2 Iron Sulphate — 6 parts
c37.s3 Paper, Ink, Soap, Cosmetics, Etc. — 13 parts
c37.s4 Cosmetics and Perfumery — 19 parts

Chemistry In Practical Arts (Ii)

We have already referred to an extensive use of copper, bronze and brass in ancient India during the Ayurvedic Period for making household utensils, weapons, and images of idols for worship. We shall deal here with their uses for the construction of guns and cannons by casting during the Mogul rule. Babar, the first Mogul Emperor, who first introduced guns in India, has given an account of the casting of a copper gun in his well-known memoirs. Babar writes: "Around the mould they had erected eight furnaces for melting the metal (copper). From the foot of each started a channel which ended in the mould. The fused metal rushed into the mould through these channels like boiling water, till the mould was filled up. * * * * A day or two afterwards when the mould had cooled down, it was opened. * * * * The bore of the piece had no fault and a chamber could easily be made in it. The body of the cannon was then uncovered, and a certain number of artificers were set to finish it. * * * * * * * * * *". Brass and bronze were subsequently used in quantities for this purpose It is stated that early in Aurangjeb's reign there were in the field with the Emperor some seventy pieces of heavy artillery, made mostly of brass. Some of these were so heavy and large that they had to be drawn and moved about with the help of 20 yoke of oxen.

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As one of the notable brass guns of the Mogul time, mention may be made here of the "great gun of Agra", which had an enormous body of 14 ft. in length, and 22½ inch in bore, into which a man could easily enter in a crouching position Its weight was 1049 cwts., or 1469 maunds. It was lying near The provided image is completely blank, containing no visible text, page furniture, or images to transcribe.

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Fig. 31. *Malık-ı-maıdan*, bronze cannon at Bijapur (Neogi, *Copper in Ancient India*).

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the bank of the river Jumna outside the fort at Agra Many of the Mogul guns and cannons were later on captured by the English. It is stated that a fine 72-pounder of brass, as well as 76 brass and 86 iron guns of different kinds, were seized at Agra by Lord Lake. Sixty-eight guns and mortars of brass, cast in India, were also captured by him at Delhi

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But the most important gun of the Mogul time is the famous *Malik-i-maidan* (lit. monarch of the plain), made of bronze (Fig. 31). According to Fergusson and others it formed the largest piece of ordnance in the world at their time. The material of the gun on analysis revealed the following composition: Copper, 80.43; tin, 19.57 per cent. The dimensions of the gun are given by. Length, 14'-3"; diameter at mouth, 4'-10"; diameter at nozzle, 4'-5"; diameter at bore, 2'-4½". This huge piece of armament is now lying at Bijapur. The surface of the gun was chased after casting, and its muzzle worked into the shape of the head of a dragon, having open jaws with small elephants between It is said to be cast at Ahmednagar in 1548 during the reign of Sultan Burhan Nizam Shah. The manipulation and skill, involved in casting such a gigantic piece of bronze armament, reflects no small credit to the workers of those days.

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Many brass guns of smaller size, belonging to the Mogul period, are still to be found in different parts of India. Some of these, cast in the 16th century and known as Isa Khan's guns, have been discovered in Bengal. An analysis of a piece of metal from one of these shows the following composition: Copper, 87.72; zinc (with small quantities of iron), 10 32; tin, 1.83 per cent.

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(The above account is taken from Neogi's *Copper in Ancient India*; p 38-39.)

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Indications exist of mining and smelting of copper ores in the Singhbhum district of Bihar to have been carried on from a very early period. The evidence available points to the Seraks or lay Jains as being the persons who, perhaps 2000 years ago, initiated the mining. (*Cf. Proc. Asiatic Soc. Bengal*, June 1869, p. 170).

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Mining of copper ores and the extraction of the metal had been carried out on a large scale in the various states of Rajputana (Rajasthan) from a very early time till towards the end of the 19th century. The process in vogue during the later ages has been described in Ball's *Economic Geology of India*, as given below.

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"The pounding or crushing was effected on a stone anvil with a hammer weighing eight or ten seers; when completely reduced to powder, the ore was made up into balls with cow-dung and roasted. The blast furnaces (Fig. 32) were prepared in the following manner. A quantity of common sand was spread on the door of a circular hut, in the centre of which a depression, 12 to 15 inches in diameter and 2 or 3 inches deep, was made; in this a layer of fine sand and another of ashes were laid to prevent the metal from adhering to the bottom of the receiver; two clay nozzles or tuyers were then placed on opposite sides of this hollow and a third between them, leaving the fourth side vacant for the slag to escape The nozzles were then connected by moist clay; and a circular rim of mud, a few inches in height, was raised, on which three annular vessels of fire-clay were placed to form the body of the furnace Each of these was 15 inches in external diameter, 10 inches high, and 3 inches thick. They were used repeatedly, but the lower part of the furnace had to be reconstructed for every charge. The bellows were simply goat-skins connected with the nozzles, and were worked by the families of the smelters. After a preliminary firing to dry the mud, the furnace was charged with charcoal, roasted ore and iron slag, the latter being employed as a flux. In a day of nine or ten hours' duration, 3 maunds of charcoal, 2½ of the roasted ore and 2 of the iron slag were consumed. The slag was drawn off, and the smelted copper, which had accumulated at the bottom of the furnace, was removed on the following day It was then remelted and refined in an open furnace under a strong blast from bellows,

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Fig. 32. Copper reducing furnance at Khetri (Ball, *Economic Geology of India*).

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and cast into small bars or ingots, which were subsequently removed to the Mint and cut up and fashioned into coins."

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"The ore was said to yield only from 2½ to 7½ per cent. of metal. The quality of the metal is said to have been inferior to that of Basawar, this being attributed to the use of the iron slag as a flux .".

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Iron and Steel

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An account of the ancient historical specimens of iron in ancient India of the Ayurvedic period has been given before. We propose now to dwell on the specimens and products of the later ages.

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Of these, the iron pillar at Dhar, the ancient capital of Malava, deserves our first and foremost attention. A full account of this pillar has been given by H. Cousens in the *Annual Report of the Archæological Survey of India*, 1902-03 (pp. 205-212). The Dhar Pillar (Fig. 33) is much larger than the famous Delhi Pillar, of which we have already discussed before. This pillar had a length 43′-8″ as against 23′-8″ of the Delhi Pillar. It is now lying broken in 3 pieces at different places. The first and the largest piece, 24′-3″ in length and square in cross section, lies half-buried near the northern gate of the 'Lat Masjid' which was built near the pillar itself by Sultan Dilwar Khan in 1405 A D. The second piece, 11′-7″ in length, now lies in the courtyard of the Ananda High School; its shape is not uniform, 8′-6″ being square and 3′-1″ octagonal. The third piece lies embedded in the masonry foundations of the public garden named Lalbag. It has a length of 7′-6″ and is rectangular in cross section. The average width is 10 25- inches Several small holes surround the pillar, but they are not uniformly distributed The weight of the pillar is estimated to be seven tons, one ton greater than that of the Delhi Pillar. It is believed to have been constructed in the 12th century A.D. as a victory pillar. Like the Delhi Pillar, this is also evidently made of wrought iron and in a similar manner. Cousens is of opinion that the holes or pits in the body of the pillar were made as the result of inserting some instruments like crowbars, while the pillar was being forged and welded.

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There is another iron pillar, 12′-9″ high, situated in the courtyard of the temple of Achaleswar on mount Abu in Rajputana. The pillar (Fig. 34) has a Saiva trisul or trident at its top and is evidently made of wrought iron in a manner similar to that of the Delhi and Dhar Pillars. It is stated that the pillar was built in the 14th century as a monument of victory.

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In the temple of the sun-god at Konarak in Orissa, which is more or less in ruins, there are quite a large number of iron beams of great dimensions (Fig. 35) Some twenty-nine of these have been counted, the largest one having a dimension of 35 feet in length and 7 to 7½ inches in width with a square cross section. The beam has an approximate weight of 6000 lbs. There is another beam measuring 23½ feet in length and 11 by 10½ inches in section, which was possibly a part of a much larger one. It is stated that the temple at Konarak was built partly in the latter half of the 9th century A.D. (the main temple) and partly in the first half of the 13th century A.D (the *natmandir* and the minor temples).

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In the temple of Juggernath at Puri in Orissa, which was built in the 12th century A.D., iron beams of quite large dimensions have been extensively used both in the main and the garden temples. In the latter as many as 239 iron beams have been counted. These range up to 17 feet in length and to 6 by 4 or 5 by 6 inches in cross section.

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The iron used in making the beams for these Orissan temples is pure wrought iron. An analysis of a specimen from Konarak beams by P. Neogi gives the following results :

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Fig. 33. Iron pillar at Dhar (Neogi, *Iron in Ancient India*).

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[Figure: Fig. 34. *Iron pillar at Mount Abu* (*Neogi, Iron in Ancient India*)]

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[Figure: Fig. 35. *Iron beams at Konarak* (*Neogi, Iron in Ancient India*)]

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| Specific gravity :— | | 7.8 |
| Iron | .... .. | 99.64 per cent |
| Carbon | . | traces |
| Sulphur | . ... | traces |
| Phosphorus | .. | 0.15 „ |
| Manganese | ... .. | nil |

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The composition is, therefore, very similar to that of the iron of the Delhi Pillar. But while the iron pillar at Delhi, as reported before (*vide*, p. 100), shows immunity to rusting even after centuries, the iron beams of the Konarak temple are more or less severely corroded. This seems to suggest that the moist and salt-laden air of the Orissan sea coast possibly provides a more favourable condition for corrosive action. This has been corroborated by the recent work of J. C. Hudson† of British Iron and Steel Research Association, who investigated the causes responsible for the remarkable resistance to corrosion shown by the Delhi Pillar, which has long been a subject of great scientific interest. Hudson has shown that the relative humidity of the air at Delhi seldom exceeds 70 per cent, which, according to the classical researches of W. H J. Vernon, serves as the critical limit for the atmospheric corrosion of iron and steel to set in. This should, therefore, lay to rest all speculations, and eliminate all hypothesis, regarding the alleged intrinsic superiority of the iron of Delhi Pillar, so far as its corrosion resistance is concerned.

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† *Nature* 172, 1953, p 499

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P. K. Gode, in his article on the “Use of guns and gunpowder in India from A.D. 1400 onwards”, adduces evidences in support of the view that guns were in use in India since 1400 A.D Mahun, a Chinese traveller, visiting Bengal in 1406 A.D., mentions that guns were to be seen in Bengal at that time. In the *Ancient Monuments of Kashmir* by R. Kak it is stated that fire-arms were first introduced into Kashmir in 1466. The employment of a force of musketeers and gunners at the siege of the fort of Champanar by Mahmud Bagda in 1482 is recorded in the *Hindoo Annals of Gujerat* by A D. Forbes.

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In memoirs of Babar we find that he used cannons and gunpowder near Kanauj in 1528

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Description of iron guns and cannons are found in the Sanskrit work, entitled Sukraniti, or the 'Elements of Polity', by Sukracharya, which is possibly a compilation of the 16th century A D., though some authorities are inclined to place it at a much earlier date. *Sukraniti* describes two varieties of fire arms: *kshudra nalika*, small guns or match-locks, and *brihat nalika*, large guns or cannons. *Kshudra nalika* is 2½ cubits long, having a longitudinal bore of the thickness of the middle finger and provided with two raised points for the purpose of taking aims. These small guns were furnished with wooden handles *Brihat nalikas* or big guns had no wooden handles. They were moved about in carriages, and their range depended on the thickness of the metal plate and bore, as well as on their length.

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We would now proceed to describe some specimens of very big iron guns of the Mogul days, found scattered in different parts of India. Most of these weigh about 30–47 tons. The maximum length found is about 31 feet, and the longest bore reaches about 1 ft. 7 in diameter. These guns were generally constructed of iron bars of square section laid longitudinally along the bore, over which iron rings were slipped, one at a time, while red hot. On cooling, they shrank and fastened the iron bars strongly together. Near the breech the guns were often strengthened by a second layer of rings

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Many big iron guns have been found in different parts of Bengal, notably at Dacca, Murshidabad, Bishnupur and other places. A gigantic gun of hammered wrought iron was found at Dacca, which contained 234,413 cubic inches of the metal and weighed approximately 30 tons. The weight of an iron ball from this gun was found to be about 465 pounds. But the gun has disappeared now, having fallen into the river long ago, together with the bank on which it was placed. It is stated that this gun was mentioned under the name of *Kaley Khan* by the Venetian traveller Manucci in the list of big cannons possessed by the Moguls in the 17th century.

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There is a big iron gun at Murshidabad, named *Jahan-kosha* (conqueror of the world). It has a length of 17 ft 6 in. and a circumference of 5 ft. 3 in. (Fig. 36). From the inscription on the brass plate on its body, it is ascertained that the gun was constructed in 1637 during the reign of Emperor Shajahan.

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In Bijapur there are some very big guns of the Mogul time. The famous *Landa Kesab* gun (Fig. 37) lies still on the south wall of the city. It is 21 ft. 7 in. long with a diameter of 4 ft. 4 in. at the breech. Its calibre is 1 ft. 7 in. and the bore length 18 ft. 7 in. The weight of the gun is estimated to be 47 tons.

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There is another long gun, called the *Farflier* at Bijapur, raised on the huge tower known as the Haider Burj. It is 30 ft. 8 in. long and has a bore of 1 ft. in diameter.

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Finally, mention may be made here of the long gun at Gulbarga in Hyderabad (Fig. 38). It has got a double row of iron rings, ten on each side, by means of which the gun was possibly conveyed from one place to another.

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Innumerable small muskets or iron match-locks (*bundooks*) of the Mogul days can now be found in the museums in different parts of India and in the treasure houses of Indian princes and landlords. It is stated in the *Ayeen Akbari* (an important administrative record of the reign of Emperor Akbar) that excepting Rum (ancient Turkey) no kingdom could compare with the Indian Empire under the Moguls in the number and variety of its ordnance. It gives a description of the manufacture of *bundōōks* from wrought iron.

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“*Bundooks* are. now made in such a manner that when filled with powder up to muzzle, there is no fear of their bursting. Formerly, they never were of more than four folds of iron, and sometimes only of one, joined together by the two extremities.

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of the breadth, and they were very dangerous. His majesty (Emperor Akbar), after having the iron flattened, has it rolled up like a scroll of paper, but slantingly, and every fold is passed through the fire. There is also the following method: solid pieces of iron are properly tempered and then bored with an iron borer; and three or four of these are joined together to form a bundook. In preparing the iron for bundooks half is lost in the fire." (*Ayeen Akbari*, Gladwin's Translation, Vol. I. p. 111.)

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Reference has already been made in a previous section on 'Chemistry in Practical Arts' to the fact that steel had been prepared in Hyderabad, Mysore and Salem and other parts of Madras Presidency in India from a very early time, and it constituted the metal from which the famous Damascus blades were made. This steel was exported to Persia and the European countries under the name of *wootz* (*cf.* p. 102).

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In Yuktikalpataru, a manuscript of the eleventh century, we find a list of places where swords were manufactured from Indian steel. Benaras, Magadha, Ceylon, Nepal, Anga, Mysore, Surat and Kalinga (Orissa) are the names of places mentioned therein. It also describes the qualities of the swords manufactured in those localities. A similar reference is also found in the Sarangadhara Paddhati, a work believed to be composed in the 14th century by the alchemist Sarangadhara. It mentions the following places noted for the manufacture of swords: viz., Khatikhattara, Rishi, Bānga (Bengal), Shurporaka, Videha (Mithila or Trihut), Anga (Bhagalpur), Madhyama-gram, Bedidesha, Sahagram and Kalinjar. Dimensions and qualities of the swords, as well as the varieties of iron and their different colours, have been discussed in these two treatises.

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Tinning and Alloying

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The use of tin for coating household metallic utensils as a protection against acid food and metallic (copper) poisoning, may be said to have gained currency in India from the middle ages, possibly after the advent of the Muslims. The term *kalai*, The provided image is completely blank. There is no text or content to transcribe.

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Fig. 36. Iron gun at Murshidabad (Neogi, *Iron in Ancient India*).

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*Fig 37 Landa Kesab gun at Bijapur (Neogi, Iron in Ancient India).*

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Fig. 38. Iron gun at Gulbarga, Hyderabad (*Neogi, Iron in Ancient India*).

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current in many parts of India, means tin-coating. The process is usually carried out by a class of people known as *kalaiwalas*, some of whom have regular shops, while others move from house to house Reference may here be made to an article by P. K. Gode of the Bhandarkar Oriental Research Institute of Poona, on the "History of tin-coating of metallic utensils in India between A.D. 1300 and 1900".

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A copper container with coating of tin on both the surfaces—exterior and interior—has been found at Kolhapur (Brahmapuri excavation). The date, ascribed to it, is A D 1347–1500.

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Abul Fazl in *Ayeen Akbari* has written of tinning copper vessels for his Majesty's (Emperor Akbar) use.

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It may be noted here that the term *kalai* is adopted clearly from Arabic *calai*.

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An alloy of considerable interest, produced in India since the Mogul period, has been named *bidery*, from Bider, a town 60 miles north-west of Hyderabad. It has a blackish colour and is composed of copper, lead and tin (8 : 2 : 1). These are melted together, mixed with spelter or zinc (16 parts for every 3 parts of the alloy) and the mixture melted again. It is then dipped into a solution of sal-ammoniac, saltpetre, common salt and blue vitriol, when the surface of the alloy turns black. According to another process zinc, copper and lead (30 : 1 : 1 approx.) are melted together, and a mixture of resin and beeswax added to the mass in the crucible to prevent calcination. It was then poured into a mould made of baked clay. The article was finally turned in a lathe. Artists then inlay flowers and other ornaments of silver or gold. The article is first rubbed over with sulphate of copper and water to give the surface a blackish colour, which makes it easier for the artist to distinguish the figure drawn by him. The cavities are then filled up with small plates of silver which adhere firmly to the *bidery*. It is then polished and stained. Vases, basins, cups, etc., are made of it. Some *bidery* is also made in the N. W. India and some in Bengal.

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Enamelling

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The art of enamelling or fixing colours by melting in fire has been known in every part of India since the middle ages. It is chiefly employed in ornaments and jewellery of gold and silver.

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In general 10 parts of lead and 3 parts of tin are oxidized by continued heat and exposure to air. To the mixed oxide are added 10 parts of powdered quartz and 10 parts of common salt. The mixture is melted in crucibles. A white enamel is thereby obtained, which forms the basis of coloured enamels A soda-lead glass with tin oxide in suspension is thereby produced. The metallic oxides are added to this for colouring. The oxides of lead or of antimony produce a yellow enamel. Red enamels are obtained by a mixture of the oxides of gold and iron. The oxides of copper, cobalt and iron give green, blue and violet respectively, and a variety of intermediate colours by mixtures.

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Recovery of Gold from the Wastage of Gold Working

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From the time of Emperor Akbar, and possibly even earlier, some processes have been in vogue in India for the recovery of gold from the waste that results in the course of preparing jewelleries These are generally carried out by more or less illiterate people of the artisan class.

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In joining together the parts of jewellery, a certain amount of gold is lost with the pieces of solder which fly off before the blow-pipe; a little loss also occurs by volatilization, as the solders usually contain zinc. The operations of filing and cutting lead to a further loss by mechanical causes. But an appreciable loss of gold occurs during the chemical operations of the goldsmith, which consist in cleansing, colouring and polishing of the articles. The gold employed for making jewelleries is never pure, as pure gold is too soft for working An alloy of gold and copper is always used for the purpose.

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During heating, the surface of the article is blackened due to oxidation and formation of cupric oxide. This is intensified by hammering in the intervals between repeated heating Mention may be made in this connection of a particular artifice, which is sometimes employed by the goldsmiths to cleanse the surface of a gold-copper alloy that has been blackened by fire. It is found that if a blackened piece of gold copper alloy be heated in a charcoal fire to redness, and then water be sprinkled on the fire, the alloy at once acquires the bright colour of gold. The explanation of the phenomenon seems to be that, when placed in a charcoal fire, the cupric oxide is reduced to metallic copper But if it is taken out when hot, it comes into contact with the air again and is oxidized What the goldsmith does, is to suddenly cool down the metal when in the reduced state, and not to allow it to come into contact with the open air unless it is quite cold. This prevents reoxidization and hence blackening

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The gold ornaments are usually coloured bright red or orange, and sometimes reddish violet. The process of colouring, as practised by the goldsmiths or by the *rungwalas*—a class of people whose sole business is to colour ornaments or other articles of gold, involves rather cumbrous and complicated chemical operations. The process may be briefly described as follows. The articles are first cleansed of all external dirt, as well as of the blackness, due to the formation of cupric oxide on the surface when heated in a charcoal fire. They are then placed in a bath of boiling concentrated decoction of unripe fruits of tamarind (*Tamarindus indica*). This liquid contains considerable amount of tartaric and other acids in the free state. These acids dissolve away the copper oxide from the articles, leaving a yellow surface of pure gold. This is indicated by the fact that the solution of the tamarind pulp becomes distinctly blue in virtue of the formation of copper salts This treatment also removes the oxide of zinc from the soldered surface. The articles, thus cleansed, are then covered with a thin layer of a paste, made of equal parts of common salt and potash alum, and afterwards placed on the fire. After the paste is dried up, it is washed off with water. The colour of the gold is thereby somewhat improved, as this treatment removes any particles of oxides of copper still remaining on the surface.

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As a result of the above treatments the articles acquire almost the beautiful yellow colour of pure gold: but the soldered surface appears at the same time as white as pure silver. This defect is then remedied by the next process to be described now. A mixture consisting of four parts of nitre, one part of common salt and one part of alum is added to water in an earthen pot. The amount of water used is such that about half the amount of salt mixture remains undissolved. The solution is then heated till it boils, evolving large quantities of gases and fumes, which obviously contain chlorine as a constituent. In this boiling solution the cleansed articles are kept immersed for a time, till a layer of shining gold is formed on the surface of the white solder, and the entire surface presents the appearance of being formed out of a homogeneous material. The articles are then taken out and washed. The reactions that occur during the above process may be explained as follows. When the salt mixture is boiled with water, chlorine and nitrosyl chloride are evolved. These act upon the gold forming a solution of gold chloride. The latter coming in contact with the white soldered surface deposits gold upon the latter, masking its white colour. It is clear that a considerable amount of gold is lost by solution in this treatment. The residual fluid, containing the dissolved gold and known as *jamak*, is, therefore, considered valuable and sold to a class of people called *jamakwalas*.

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The articles, after being removed from the boiling *jamak* solution, are thoroughly washed and rubbed with a brush. They are then ready for treatment in another bath. This consists of a solution of tamarind pulp, nitre and common salt in water, which is placed in an earthen pot on fire and heated to ebullition. A little sulphur is then added after which the articles are placed in the liquid. The sulphur is added in a finely divided state obtained by rubbing a stick of sulphur with a little water on a piece of slate. Care is always taken to add an insufficient amount of sulphur at first, for it is found that the shade of colour that is produced on the gold depends solely on the quantity of this ingredient, which accordingly requires exceedingly careful regulation. The colour of the articles is now examined from time to time, adding more sulphur gradually for increasing the depth of colour. When the requisite shade of colour is reached, further addition of sulphur is stopped. The boiling is continued for some time more, after which the articles are taken off the solution and given a final wash and polish. Addition of too much sulphur renders the colour deep violet and finally black The chemical reactions, that occur during this stage of colouring, are rather obscure. P C. Ray, in his book, has suggested a tentative explanation to account for the formation of violet colour on the surface of the metal by the treatment described. According to this view the solution of nitre and common salt, when boiled along with the acids from the tamarind pulp, is likely to liberate chlorine. This attacks the gold, giving rise to auric chloride in solution: the addition of sulphur serves to remove the excess of chlorine, due to the formation of sulphur chloride. The auric chloride slowly breaks up into aurous chloride by heat, and the liberated chlorine is taken up by sulphur. The aurous chloride is then changed into aurous oxide, which is deposited in the form of a thin violet layer on the surface of the articles The explanation appears to be a very probable one, as aurous oxide possesses a dark violet colour and is produced from auric chloride, when a solution of the latter is boiled with salts of organic acids. A considerable amount of gold is also lost in this process.

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We shall now proceed to describe the methods employed for the recovery of gold that is lost during the above processes of working of gold for the making of jewelleries and ornaments by the goldsmiths In Bengal, for instance, there are two small classes of people who have been earning their livelihood for a long time by recovering gold from the refuse and waste liquors of goldsmiths' shops. These are known by the names of *neharwala* and *jamakwala*.

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It is a common practice in every goldsmith's shop in India that the daily sweepings and other refuse of the rooms are never thrown away, but stored up carefully in one place The heap of rubbish and dust, thus accumulated from day to day, are finally sold to *neharwalas* (from *nehar*, which means sweepings). The heap of rejected earthen crucibles, employed for melting gold, is also sold to them. Sometimes the soot hanging from the ceiling and walls is also purchased. Even the dust collected by shaking the workmen's mats, as well as the sweepings obtained from the space underneath, are sold to the *neharwalas*

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The heap of dust and the refuse matters are ground fine by the *neharwalas*. The crushed materials are soaked in water in a big earthen pot for several days. They are then agitated with a large amount of water, when the lighter earthy materials float and remain in suspension, whereas the heavy metallic particles settle at the bottom. The supernatant water with its earthy suspension is then allowed to run out. The process is repeated till the solid matter is reduced to a small bulk. The residue is then dried up either in the sun or on fire The dried remnants of several washings are mixed together, and the mixture is washed once again. The metals present in the washed mixture generally include iron, which is removed by picking out with fine pincers. In later days, the use of magnet for the purpose has come into vogue. The mixture is then melted in a large crucible. The earthy matter sticks to the sides of the crucible, while the metallic portion melts and falls to the bottom. A button of gold, silver, copper and zinc is thus obtained. Gold is then extracted in a pure state from this alloy. For this purpose, the alloy is beaten into thin leaves Each leaf is then covered with a thin layer of a paste of brick dust and common salt. The leaves are finally arranged one above another and exposed to the heat of a fire. After a certain number of days, depending on the nature of the alloy and the temperature of the fire, the gold is found to be very nearly pure. This method has in the later ages been entirely superseded by the far easier and more economical process of treating the alloy with strong nitric acid. For this operation, however, the alloy must be reduced to a fine state of division. This is effected rather ingeniously by melting the alloy and then suddenly dropping the molten metal into water. By this means the metal is at once reduced to a fine powder

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It has already been stated that a considerable amount of gold is lost during the processes of cleaning and colouring the ornaments. The waste liquor after these treatments, known as *jamak*, is sold to the *jamakwalas*. Gold is recovered from the *jamak* by the *jamakwalas* by a process, briefly described below. The waste liquor or *jamak* is boiled in an earthen vessel to reduce the volume. When practically the whole amount of water has been evaporated off, the viscous mass is removed to an open earthen vessel. This is then mixed thoroughly with a small quantity of borax and a large quantity of a substance, known as *poonoor* (a mixture of partially oxidized lead, copper and zinc with traces of silver and iron). The mixture is made into balls of about 2–3 inches in diameter with the addition of sufficient cow-dung. The balls are then dried perfectly in the sun, or over fire. Poonoor is a by-product, obtained during the purification of silver when alloyed with copper and other metals. For this purpose, the alloy of silver is mixed up with a large quantity of lead, and the mixture is melted on a small hearth; air is then blown over the molten mass, when the pure silver separates and collects at the bottom. The partially oxidized lead, together with impurities originally present in the silver, constitutes what is known as *poonoor* This operation for the purification of silver resembles practically that of cupellation.

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The balls containing the waste gold, as prepared above, are placed in a small hearth, the interior of which is covered with a layer of slaked lime about half an inch thick. The hearth is made by scooping out on the earth in an open place a hollow of the shape of a hemisphere about a foot in diameter. A powerful charcoal fire is produced over the balls in the hearth, which is aided by blowing air with two or three large pairs of bellows A large metallic mass ultimately collects at the bottom of the hearth, consisting mainly of lead. As the blowing is continued, lead is oxidized to litharge and gradually blown off. As the whole of the lead has passed off in this way, a mixture of gold, silver and copper remains behind.

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The *jamak* or the waste liquor was found on analysis by P. C. Ray to contain bases like silver, copper, zinc, gold, aluminium, potassium and sodium; while amongst the acids present, nitric, hydrochloric and sulphuric were recognized in large quantities. Traces of free chlorine could also be found in some of the solution, while perceptible amounts of iron were found in almost all A microscopic examination of the material revealed octahedral crystals of alum, rhombic prisms of nitre, and the cubic crystals of common salt Besides these, there were observed small numbers of long, transparent needles of the crystals of NaAuCl₄.2H₂O. Fine particles of free gold were also detected.

Gunpowder, Saltpetre, The Mineral Acids, Alum, Etc.

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That the knowledge of the art of manufacturing gunpowder was known to Indians in the 16th century A.D., seems to be supported by the several recipes given in the Sukraniti or the 'Elements of Polity' of Sukracharya. The translation of relevant verses is given below:

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"Take five palas of saltpetre, one pala of sulphur and one pala of charcoal, prepared from the wood of *Calotropis gigantea*

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In a publication on *The History of Fireworks in India* (between 1400-1900 A.D.) Gode has quoted formulae for the manufacture of specific fireworks from a Sanskrit work called the Kautukachintamani by Gajapati Prataparudradeva of Orissa, a royal author, who flourished in 1497-1539 A.D. From the manuscript of this work, as was available in the Government Manuscripts Library at the Bhandarkar Oriental Research Institute at Poona, Gode has noted down the following materials used in the manufacture of fireworks, as found in the Sanskrit verses

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Sulphur (*gandhaka*), saltpetre (*yavakshara*), charcoal (*angara*), steel and iron powder (*tikshna loha churna* and *loha churna*), copper carbonate (*jangala*), yellow orpiment (*talaham* or *harital*), ochre (*gairika*), wood of 'khadire' tree (*khadiram daru*), hollow bamboo piece (*nalaka*), wick (*bartika*), five salts (*pancha kshara*), lodestone (*akhupashan*), pulp of castor seeds (*aranda majja*), mercury (*sutam*), rice paste (*annapista*), tin or lead (*naga*), charcoal from the 'arka' wood (*arkangara*), cow's urine (*gomutra*), cinnabar (*vermilion*).

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It may be assumed as suggested by Gode (loc. cit) that some of the recipes for fireworks in India might have been brought from China and then modified by the substitution of Indian ingredients for the Chinese materials. For, fireworks, fire-arms, and military pyrotechnics were developed in China much earlier than in any other country. The Chinese had real fire-arms in the 13th century A.D., and they achieved considerable skill in manufacturing fireworks Preparation of explosive powder, containing sulphur, charcoal, saltpetre, paper, oil, etc., for military purpose, was known to them as early as 1000 A. D ¹

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¹ * L Davis and J R Ware, *Early Chinese Military Pyrotechnics*. *Journal of Chemical Education*, 24, 1947 522
* See Gode's paper on Akasabhairava Kalpa, *Karnatak Historical Review*, 1939 [^cont]

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A description of fireworks and guns also occurs in another Sanskrit work, called Akasabhairava Kalpa, found in the form of a manuscript in the Tanjore Manuscript Library. (*cf* Gode, loc. cit.)cont This treatise, according to Gode, obviously belongs to a period later than 1400 A.D

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Gode (loc. cit) has further referred to the description of a display of fireworks in a marriage procession in a Marathi poem Rukmini Svayamvara, composed in 1570 A D. by the saint Ekanatha. Varieties of rockets and other fireworks are described in the poem.

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From the description given of fireworks in India by Verthema and Barbosa in their *Travels* (1502-1518 A D ), Gode concludes that fireworks were manufactured in India on a large scale at a time near about 1500 A.D. for use during marriage ceremonies and other festive occasions

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Among the varieties of fireworks, still in use in India mention may be made of the cracker in different forms, known as *gola, patka, vengagvedi, koroo, adirvedi*, etc. Chinese fire-mixture, used in India and burnt in earthenware pots, is known as *tubri*. Other fireworks used in India are *anar, phuljhuri, burusu, chandrajyoti* or *mehtab* Rockets are known as *hawai* or *abusavanam* and called *bana* in the Sanskrit works.

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Saltpetre

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*Sauvarchala* stands for saltpetre in Rasarnava and Sukraniti. It occurs extensively in Bengal and in upper India as an efflorescence on the soil.

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Saltpetre has been in use in India from a very early time as the basis of rocket and other fireworks. In the Dasakumaracharita by Dandi (circa 6th century A.D.) mention is made of *yogavartika* (magic wick) and *yogachurna* (magic powder), of which saltpetre was probably the basis. The earliest account of the manufacture of saltpetre on a commercial scale in India, that has come to our notice, occurs in a work entitled, *The Travels of John Albert de Mandelso from Persia into the East Indies*, London, 1669. It describes the process as follows :

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"Most of the saltpetre, which is sold in Guzuratta, comes from Ajmer, sixty leagues from Agra, and they get it out of land that hath lain long fallow. The blackest and fattest ground yields most of it, though other lands afford some, and it is made thus : they make certain trenches which they fill with their saltpetrous earth, and let into them small rivulets, as much as will serve for its soaking, which may be the more effectually done, they make use of their feet, treading it till it becomes a brooth (broth). When the water has drawn out all the saltpetre which was in the earth, they take the clearest part of it, and dispose it into another trench, where it grows thick, and then they boil it like salt, continually scumming it, and then they put into earthen pots, wherein the remainder of the dregs goes to the bottom ; and when the water begins to thicken, they take it out of these pots, to set it adrying in the sun, where it grows hard, and is reduced into that form wherein it is brought into Europe."
@H pp. 66-67.

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Mineral Acids

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The distillation of alum is referred to in Rasarnava, and of green vitriol in Rasaratnasamuchchaya. We have, however, no evidence that the acid thus derived was ever used as a solvent. At the same time, it might be pointed out that Rasarnava and similar other works lay stress upon *vida*, in which aqua regia may be said to be potentially present, and which is fitly described as capable of *killing* all the metals.

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The preparation of mineral acids is incidentally described in several exclusively medical works, composed probably in the 16th and the 17th centuries; e.g. in Rasakaumudi by Madhava, Rasaratnapradipa and Bhaishajyaratnavali by Govindadasa, etc ...... In the last work under the heading of *mahadravakarasa*, directions are given for distilling a mixture of, among other things, alum, green vitriol, sal-ammoniac, saltpetre and borax in a glass retort In this way a dilute solution of nitro-muriatic acid is obtained, which is prescribed in the derangement of liver and spleen. There is a similar recipe in which, in addition to the above ingredients, rock-salt and sea-salt are used, thus yielding what is called *samkhadravaka* (lit. solvent for conch-shell).

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The term *dravaka* (solvent) seems to have been expressly coined to do duty for the mineral acids. We have seen all along that in the older works *dravaka* was used invariably in the sense of solvent or flux, but never in the sense of a mineral acid, the knowledge of which seems to have spread both in the east and the west almost simultaneously. The regular application of the mineral acids to technical operations dates from the time of Emperor Akbar or perhaps a little earlier Thus in the *Ayeen Akbari* under the "Method of Refining Silver" mention is made of the use of *rası* (aqua fortis). It is not easy to make out how much of the processes of the assay of gold and silver, as described in the *Ayeen*, is of earlier origin

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Alum and Green Vitriol

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Alum, with green vitriol, is distinctly referred to in the Susruta under the names of *saurashtraja* (lit. begot of Saurashtra—Surat) and *kasisa* respectively From the ancient times the earth of Surat has been known to yield this mineral (alum). The following synonyms of alum, *kamkshi*, *tuvari* and *saurashtraja*, are found in Amarkosha (600 A.D.) *Rasaratnasamuchchaya* also gives the same synonyms.

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As we find from Ball's *Economic Geology of India*, the old indigenous process for the manufacture of alum survived even to the end of the 19th century A.D.. "Alum is principally used as a mordant in dyeing, but as a drug its employment is extensive in India. In two localities in Rajputana alum shales occur in quantities, from which alum was prepared. A small quantity was manufactured from slates obtained in the district of Sahabad in Bihar. Copperas or iron sulphate also occurs in the same region."

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Fig. 39. Alum and sulphate of copper works at Khetri, Rajasthan (Ball, *Economic Geology of India*).

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In connection with the copper mines at Rajputana, Khetri and Singhana, considerable quantities of blue vitriol, copperas and alum were used to be manufactured till the end of the 19th century. It is stated that in 1864 A.D. there were twenty of these factories at Khetri and about double the number at Singhana. "The process of manufacture consisted in the lixiviation of the broken shales from the mine with water in a series of earthen *gharas* (vessels), arranged on ledges prepared for the purpose on the heaps of refuse. The shales were mixed with the crusts derived from the previous lixiviation (Fig. 39). Each charge of shale was subjected to the action of three changes of water; and the water itself was changed from one *ghara* to another, till it had taken up sulphates from seven different steepings. It was then of a thick dirty-bluish colour and taken to the boiling house, where it was boiled in earthen *gharas*; when sufficiently concentrated, it was left to cool; and thin sticks being introduced, the blue vitriol crystallized on them. The mother liquor was then poured off and again boiled, and on the addition of saltpetre, the alum crystallized at the bottom of the vessel. The residual sulphates still in solution were allowed to crystallize out by exposing the mixture to the sun."

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The manufacture of alum in Cutch from a pyritous dark-grey or black shale in large quantities had also been in vogue for a long time. It is stated that before 1818 the exports of alum from this source amounted in some years to several thousand tons. These mainly went to Guzerat and Bombay to be employed in dyeing. The process has been described as follows:

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"The shale is excavated from pits and is exposed for four months, a slow combustion taking place owing to the decomposition of the pyrites. It is then spread in squares resembling salt pans and sprinkled with water. After about twelve days it consolidates into efflorescing mamillated crystalline plates or crusts, called *phūlhāri-kā-bīj* or seed of alum. These crusts are boiled in large iron vessels (luted inside with lime), together with saltpetre (or other potash salt), in the proportion of 15 of alum seed to 6 of the latter; when it has settled, the liquor is placed in small earthen vessels, somewhat the shape of flower-pots, and crystallisation takes place in three days. The crystals are again boiled one or more times to concentrate the solution, which is finally ladled into large thin bladder-shaped earthen *muthas* or *gharras* with small mouth; these are sunk into the ground to prevent their breaking, and in five days the alum is found crystallised in masses. The vessels are then broken, and the alum is stored.

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"Alum is also manufactured from the water of a hot spring north of Mhurr in Cutch. The impure saltpetre, required for making alum, is obtained by lixiviation of village refuse."—Ball's *Economic Geology of India*, pp. 431-33.

Iron Sulphate

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"The green vitriol or copperas of commerce, which is known to the natives as *kahi* and *hara kasis*, is produced principally from the so-called alum shales, from which alum is prepared. As is the case also with alum, copperas is found sometimes as a natural exudation upon alum shales and other rocks, which include iron pyrites.

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"This native copperas goes by several different names in India according to the nature of the other substances with which it is combined.

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"In the year 1833, Mr. J. Stevenson published an analysis of native sulphate of iron obtained from Bihar, which was used at that time by the native dyers of Patna.

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Analytical results:—

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—Ball, loc. cit., p. 419.

Paper, Ink, Soap, Cosmetics, Etc.

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The art of paper-making was possibly introduced into India from Nepal at or about 1000 A.D. It attained a high degree of technical excellence in Nepal in those early days. It was from China that paper came to Nepal. The industry flourished in China much earlier and entered Nepal between the 7th and 9th centuries A.D., when the Chinese influences impressed themselves deeply on Nepalese culture and civilization. Nepal paper once commanded a very extensive market, and was exported southwards to Hindusthan and northwards to Sokya-gumba, Digarchi and other places in Bhote. It was used all over Kumayun and was sold at Patna, Saran, Janakpur, Darbhanga, Purnea, Gorakhpur, Balarampur and Tardah in Oudh.

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The view that the art of paper-making was brought to India by the Moghuls is no longer acceptable. No direct connection can be traced between the Nepal paper-making and the Moghul court. The process followed in Nepal differs considerably from those practised in Kashmir and the Punjab under the imperial patronage.

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Mahuan, the Chinese interpreter, who visited Bengal in A.D. 1406, stated that the people of Bengal manufactured paper from the bark of a tree, and that the paper was smooth and glossy like a deer's skin.

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During the Moghul and the Peshwa period the industry flourished throughout the whole country, mostly in the Punjab. It is said that Sialkot produced paper worth 9 lacs of rupees in Jehangir's time. Paper was produced at Multan, Rawalpindi, Jalalpur, Delhi, Lahore, etc. ... The materials employed were old clothes, old tents, the bark of certain shrubs and trees, etc. .... These materials were beaten with a wooden hammer or *dhenki*, after having been well-washed and soaked in water for several days. The pulp was mixed with a little water in a lime-lined (*chunamed*) reservoir, where the beating operation was also carried out. The workmen dip their moulds into the reservoir, and the mixture, when lifted out, instantly becomes paper. This is then removed, and each sheet is drawn through a second reservoir of water and then hung up to dry. A quality of gum arabic was dissolved in the water into which the beaten pulp was put ; the water in the second reservoir, through which the sheets were drawn, also contained that gum in the form of a mucilage, as well as some alum dissolved in it. The moulds or forms of the workmen are generally made of bamboo. The gum (gum arabic) is obtained as an exudation from a tree, known commonly as the *babool* tree.∗

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∗ References—P K. Gode—*Studies in the Regional History of Paper Industry, Migration of Paper from China to India* K B Joshi—*Paper-Making* ; All India Village Industries Association, Maganwadi, Wardha, 1944

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Soap

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Soap was possibly introduced into India by the Mohammedans, though the Hindus had made use before of alkaline lyes for a long time, obtained from the ashes of plants. They had also a substitute for soap in several berries. The crude soaps were made in the beginning from *sarjikakshara* (trona or natron), common salt, sesamum oil and goat's suet.

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Ink

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Ink was used to be prepared in early days in India, both in the solid and in the liquid form, from lampblack collected by burning linseed oil in an earthen lamp. This was mixed with the gum of *Vachellia farnesiana* and a little water, and then rubbed in an iron mortar with a wooden pestle for several hours. This paste was afterwards treated with an infusion of gall-nut in water, and the whole mass was ground again in the same iron mortar for a few hours. The pasty mass was finally dried in the sun to admit of its being made into lumps. The lumps again were further dried by sun's heat.

Linked texts (20)

Suśrutasaṃhitā — Suśruta & Nāgārjuna (siddha/alchemist), Sanskrit
Rasaratnasamuccaya — Vāgbhaṭa (alchemist), Sanskrit
Rasaratnākara — Nityanātha Siddha, Sanskrit
Rasārṇava — Sanskrit
Daśakumāracarita — Daṇḍin, Sanskrit
Tibetan translation ('Chi med mdzod) — Classical Tibetan
Bhaiṣajyaratnāvalī — Govindadāsa, Sanskrit
Konark Sun Temple
Jagannath Temple
Champaner
Agra
Lalbagh (Dacca)
Bijâpur
Dhaka
Kannauj
Pur
Kashmiri
Śārṅgadharapaddhati — Śārṅgadhara, Sanskrit
Rasakaumudī (Śrīkaṇtha Dīkṣita) — Śrīkaṇtha Dīkṣita 1600, Sanskrit
Rasaratnadīpikā (Allarāja) — Allarāja, Sanskrit