By K.Muthulekshmi – The History of Indian Chemistry
Paper presented at National Seminar on Scientific Heritage of India at the University of Calicut, Kerala from July 1-4,2000.
Human endeavour to analyse the composition of the universe and various objects is as old as civilisation. This led to the study of compositional changes effected by forces external and internal to it, and new compounds were formed by mixing two different substances. The application of this knowledge vary from pottery to medical sciences.
Evidences could be found in literary works of the period and in various scientific treatises on alchemy, metallurgy, fireworks, paper works etc. This paper attempts to chart out in chronological order such evidences beginning from the Indus valley/Harappan civilization. Various works in Sanskrit dealing with other areas of learning also point to the fact that knowledge about chemistry prevailed in ancient India. Among the 64 arts and sciences enumerated in Kamasutra of Vatsyayana there is mention of suvarna ratna pariksa (the examination of gold and gems), dhatu vada (chemistary and metallurgy), and maniragakarajnanam (knowledge of mines and quarries, and the colouring of gems and jewels).
This paper attempts to chart out the evidences and mentions found in various texts dating from the prehistoric times in chronological order.
Indus valley and Harappan Civilisation (from Pre-historic times to 1500 BC)
Archaeological evidences indicate that chemistry was the basis of many material practices during the Indus valley civilization. Pottery, important among them, has a prominent place in the history of Indian chemistry. Those pots were hardened by burning clay in fire; various processes involving minerals like prolonged heating, melting and evaporating were developed during this period. Along with these, the processes of moulding, colouring etc were also developed. A mixture of iron was used in the colouring of pots. Paintings were done with haemarites mixed with manganese. The standardization in the production of pottery is also noteworthy.
Knowledge of fermentation, manufacturing of glass etc also deserves mention.
It is possible that the metals like bronze, copper, lead, silver, gold and electrum were known to the people of Harappan civilization.
Vedic period (B C 1500 – 1000)
Rgveda mentions metals like gold, copper, silver and bronze. A golden earring and necklace are mentioned thus: Hiranyakarnam manigreevam 1
Sukla yajurveda speaks of tin and lead also: hiranyam cha meayaschame seesam chame thrapuschame syaaman cha me loham cha me 2
Chemists opine that all these metals can only be obtained by complex chemical processes: Each of these metals has different physical and chemical characteristics and need different types of extraction processes to get them out of their ores. No superfluous knowledge on the ore can give such names for the metals unless they were produced. 3
Atharvaveda compares the colour of the universal power with that of metals: His flesh has the colour of syama (iron), blood has the colour of loha (copper), totally he has the colour of tin and has the smell of lead. 4
The technique for metallurgical alloying presented in Chandogya upanisad is like this: One would join gold with the help of borax, silver with gold, tin with silver, lead with tin, copper with the help of lead, and timber with copper and leather.5. According to N Gopalakrishnan, this technique is used till now for reducing the melting point of the metals to be alloyed.6
The fact that rgvedic people knew fermentation of drinks is evident from the hymns praising somarasa. There are about 120 hymns praising it. 7
Post vedic period (600 BC – 800 AD)
This period was the flourishing age of Indian Chemistry. Various schools of philosophy, especially Samkhya, Nyaya and Vaiseshika, Arthasastra of Kautilya, Brhat samhita of Varahamihira and Ayurvedic texts like Caraka Samhita and Susruta samhita provide a lot of evidence regarding the advanced practices of Indian chemistry during this period.
Philosophical systems, as part of analyzing the universe and the objects in it, developed certain theories relating to chemistry also. The concept of five elements as the basis of material universe was generally accepted by most of the philosophical systems. This concept points to a classification of substances on the basis of their properties and states of aggregation. Earth, water and air may be viewed as comprising all elements of chemistry in the solid, liquid and gaseous states respectively.
The Samkhya system of philosophy has a unique place in the history of thought because it embodies the earliest cogent and comprehensive account of the process of cosmic evolution, based on the conservation, transformation and dissipation of energy.
The Nyaya and Vaisesika schools (BC 200) formulated the theory of paramanuvada of atomism maintaining that the basic composition of substances was paramanu-s or atoms. Paramanu-vadins probed into the constitution and properties of matter. Kanada, the exponent of Vaisesika philosophy maintains the eternity of atoms. He also explains their existence and aggregation. According to Tarkasamgrahadeepika, a text on Nyaya, the mote which is seen in a sun beam is the smallest perceptible quantity. Being a substance and an effect, it must be composed of what is less than itself, for the component part of a substance that has magnitude must be composed of what is smaller, and that smaller thing is an atom. It is simple and uncomposed, else the series would be endless.8 The atom is reckoned to be the sixth part of a mote visible in a sunbeam.
Two earthly atoms constitute a double atom of earth and by the union of three binary atoms, a tertiary atom is produced and by concourse of four triple atoms, a quaternary atom and so on to a grossest mass of earth. The qualities that belong to the effect are inherent in the integral part of primary particle.9
The dissolution of substances occurs inversely. When some action is induced in a substance by pressure attended with velocity or by simple pressure, disjunction ensues. And then the integral substance consisting of those members is resolved into its parts and is destroyed, for it ceases to exist as a whole. 10
Kanada has elaborated the qualities of substances also. P C Ray points out that the definition of light as a substance hot to feel (Tarkasamgraha) is something remarkable, which has the implication that heat and light are identified as one substance. 11
According to Vatsyayana (4th Century AD), chemical change may occur either by the application of external heat or internal heat.12 In Kiranavali, Udayana (11th Cent AD) considered solar heat to be the ultimate source of all heat required for chemical changes of earth. He thought that solar heat was the cause of change of colour of grass13, ripening of mangoes, changes in smell, taste and colour. Rusting of metals (surya paka) and conversion of food into blood were also caused by it 14. All these are instances of chemical transformation by heat.
Arthasastra (3rd Century BC)
Arthasastra of Kautilya is considered to be a mine of knowledge , which is true in the case of Indian chemistry also. There are a number of references in it about mines and factories, the characteristics and origin of the ores of gold, copper, silver, lead and iron. The Superintendent of Mines was called СakaradhyaksaТ. He is supposed to have knowledge of the methods of finding the source of ores, the veins of metals and their quality.15 The kinds of metals obtained from the mines are also mentioned. During KautilyaТs time treasury had its own mines.
The melting of metals was called dravana or vipalana . Solidification of metals is termed mrthi .16 Heating was the most important process in the alloying metals. Descriptions of the characteristics of the ores of silver, copper, tin and iron are given in the Arthasastra17. coins were made using different metallic alloys. The various impurities found in ores are also referred to.
One can also find the description of fermenting alcoholic liquids also in Arthasastra.
Important ayurvedic texts like Caraka samhita and Susruta samhita (1st Cent. BC) speak of chemical aspects of the functioning of human body, digestion, and that of medicines.
Caraka classifies objects into three, viz., animal products, vegetable products and products pertaining to earth.
He describes the nature and preparation of alkali (kshara) and gives a few instances of minerals and metallic preparations. Certain minerals like sulphate of copper, sulphate of iron, realgar, orpiment and sulphur in combination with vegetable drugs are prescribed by him for external application for cases of ring worm, eczchema, leprosy etc. 18 He speaks of pill iron compound 19, powder of pearl compound 20and iron, gold and silver tonics 21. Rayasana cikitsa prescribed for longevity etc includes many of these metallic preparations.
The portion in Susruta Samhita, which explains the preparation and use of alkalies, occupies a prominent place in Indian medical chemistry. It is said that alkalies were used to clean surgical instruments, which were used to cut the diseased parts of human body. (the term СksaraТ itself means Сthat which removes away the affected parts of the bodyТ). Plates of iron, silver and gold were dipped in alkaline liquids before mixing with medicines. Susruta classifies alkalies into mrdu, tiksna and madhyama. He gives the preparation of each category. Some of them are used for external application and some for internal administration. They are used externally for skin diseases like kusta, tumors, piles etc. and internally for abdominal tumors, indigestion, urinary deposits, intestinal worms etc. devices to store them are also advised. According to him, the sharp, saline taste of alkali when mixed with acid becomes very mild and gives up its sharpness. That is why acid neutralises alkaly.
Different metals like bronze, iron, gold, silver, lead, copper, tin and different salts like rock salt, sea salt etc are enumerated in the Samhita. Roasting of iron and other metals so as to render them fit for internal administration has been described. The thin leaves of metals were plastered with a paste of the salts and afterwards subjected to roasting and were converted into their respective oxides, chlorides or oxichlorides. This can be considered a crude process for the preparation of the metallic salts.22
Brhatsamhita (6th Century AD)
Varahamihira, in his Brhatsamhita, refers to mordants like alum and sulphate or iron for the fixing of dyes on textile fabrics. It also alludes to cosmetics, scented hair dyes, perfumes etc. It also contains information on various cement preparations, which may be classified under two heads: rock cement (vajralepa) and metal cement (vajra samghata). These varieties of cement were applied to the walls and roofs of temples and other buildings.23
Alchemy in Tantric Period (800 AD to 1600 AD)
The flourishing of chemistry in India, especially alchemy, has an interesting phase during the period of tantra. The tantric cult in India was an admixture of alchemical processes on the one hand and grotesque rites on the other, centred on the worship of Siva and Parvati. We also have a class of tantras, which is an admixture of Buddhist and Saiva cults. Rasaratnakara ascribed to Nagarjuna belongs ato this category. According to tantric cult, a man should preserve his body by means of mercury and medicaments. According to tantrics, mercury was produced by the creative conjunction of Siva and Parvati and mica was produced from Parvati. The combination of mercury and mica was believed to be destructive of death and poverty.
Sarvadarsana Samgraha of Madhavacarya which elaborates the sixteen philosophical systems current in 14th Cent AD, includes raseswara darsana or mercurial system as one among them. According to this darsana, different preparations of mercury can enable a man to be free from old age and death, ie to obtain jivan mukti. Rasa is called parada because, it enables one to overcome the worldly affairs.24
Rasarnava of unknown authorship, Rasaratnakara of Nagarjuna and Rasaratna samuchaya of Vagbhata are some of the important works of Indian alchemy written during the tantric period. Rasaratnakara and Rasarnava are tantras pure in which alchemy is incidentally dealt with. Rasaratnasamuchaya is a systematic treatise on pharmacy and medicine. Rasaratnakara of Nagarjuna contains descriptions of alchemical processes and preparations of mercurial compounds. Extraction of zinc, mercury and copper are described by him. He also elaborates on the preparation of crystalline red sulphide of mercury (swarnasindura or makaradhwaja) which is used as medicine for many ailments.
There are also works written in regional languages like Tamil, Telugu, Kannada, Malayalam, Bengali, Marathi, Oriya and Gujarati on alchemy. Here, Tamil works on siddha vaidya, about two hundred in number, deserves mention. Works of Agastya, Nandiswara, Romarshi and Kailasamuni are important among them. A comparative study of the alchemical ideas of these Tamil and Sanskrit works has not yet been initiated.
According to tantric cult, siddhis are of two types – dehasiddhi (development of the body) and loha siddhi (development of metals). The first pertains to making mercury capable of changing the molecules of lower metals into molecules of higher metals. Mercury, which is capable of this, can certainly transform human molecules also. This is dehasiddhi. Lohasiddhi is called alchemy or dhatuvada. Dehasiddhi is obtained through lohasiddhi. Gradually, devices to refine metals led to the making of their powders, which were used as medicines.
As part of these alchemical processes, there are certain methods to purify mercury. Indian alchemists had adopted 18 methods for this purpose.25 They also make classification of chemical substances into maharasa, uparasa, datu, ratna and visa. Certain refining processes of metals and mine products, mixtures of mercury also deserve special mention.
An important feature of Indian alchemy is the description of certain plants used in alchemical processes. About two hundred plants are referred to in this connection. We get an elaborate description of the laboratories and the instruments from these alchemical works.
The metal workers in India had made complicated idols from bronze and copper. The iron pillar in Qutab near Delhi, which weighs ten tones and is 1500 years old, certain iron beams in the temples of Puri and Konarak in Orissa and Rajastan, prove the advancement of metallurgy in India.
It is to be pointed out that as part of a study of the different branches of different folk traditional knowledges of Kerala, much evidence has been found regarding centuries-old iron production in Malabar26, especially in Malappuram and Palakkad districts. The place names related to iron production (Irimpuzhi, Utthalakunnu, Alapparambu etc), the ore deposits (ayiru mada) hidden in bushes, СKeeda kallukalТ which are the sediments of iron production, and the remains of smelting points of iron production are the existing evidences of once alive iron production practices in Malabar.
Fifteenth and sixteenth centuries were famous for the manufacture of guns also.
Manufacture of Paper
The technique of paper making probably came to India from china through the Arabs by about 11th cent. AD. Before the emergence of paper Indians preserved their knowledge in tala-patras or bhurja-patras. But in about 15th cent AD paper was made by mixing lime and soda with pieces of rags. There were paper making factories in СPunjab, Bihar, Bengal, Gujarat, Mysore etc.
The Chemistry of fireworks
Books on fireworks are available in various languages like Sankrit, Tamil, Marathi and Malayalam. The various ingredients that go into the preparation of explosives were the following: saltpeter, sulphur, charcoal, iron powder, mercury, copper etc.
The theories and practices relating to Chemistry held a prominent place in different areas of learning in India. But education in India, not being secular and universal, and professions hereditary and caste-specific, the technical skills and knowledge became confined to certain sections of society. The intellectual communities in society did not have active interaction with the practitioners of various sciences like the artisans etc. Eminent scholar P C Ray points out this factor to be a major one obstructing the gradual development of Indian science.27 Another factor was colonial intervention, which destroyed indigenous sciences and knowledge systems.
1 RV 1.122..14; 1.33.8
2 Suklayajurvediya vajasaniya Madhyamdina Samihita 8.13
3 Gopalakrishanan N, 1999, Indian Scientific Heritage, Indian Institute of Scientific Heritage, Trivandrum, p. 348
4 Syamamaya asya mamsani lohitamasya lohitam trapu bhasma haritam varnah pushkaramasya gandhah AV II.8.7-8
5 Tadyatha lavanena suvarnam smdadhyat suvarnena rajatam rajatena trapu trapuna sisam , sisena loham lohena daru, daru charmana CU 4.17.7
6 Gopalakrishnan N , ibid, p. 349
7 RV I.85.10, VIII, IX
8 Tarkasamgrahadeepika, Sristipralayanirupanam
11 P C Ray, 1909, History of Hindu Chemistry Vol I, The Bengal Chemical & Pharmaceutical Works, Limited, Calcutta, p.8
12 Vatsyayanabasya IV.I.47
13 Udayana, Kiranavali, Sristisamharavidhinirupanam
14 Nyayabodhini on AnnmabhattaТs Tarkasamgraha
15 Arthasastra, 2.12.30
16 Ibid, 3.3.27
17 Ibid, 2.12.30
18 Carakasamhita III, 4-5
19 Ibid XVI,28
20 Ibid XVII, 40
22 Susrutasamhita Chapters XI, XIV
23 Brhat Samhita Chapter 56
24 Sarvadarsana samgraha, Chaukamba Vidya Bhavan, Varanasi,. P.322
25 Rasarnava , 11.213-17
26 Dirar, V H, СMalabarile UthalakalТ(Malayalam), Kerala Patanangal, Oct 1995, p.53.
27 P C Ray, Ibid, Vol I, p.195