Changes

Ancient India's contribution to science and technology include principles of chemistry which did not remain abstract but found expression in practical activities like fermentation processes, distillation of perfumes, aromatic liquids, manufacturing of dyes and pigments and extraction of sugar, extraction of oil from oilseeds, and metallurgy which has remained an activity central to all civilizations from the earliest ages. Archaeologists' findings of the Indus valley civilization showed a well developed urban system with public baths, streets, granaries, temples, houses with baked bricks, mass production of pottery and even a script of their own which depicted the story of early chemistry.<ref name=":0">Purwar, Chhavi. ''[https://www.journalijdr.com/sites/default/files/issue-pdf/7278.pdf Significant Contribution of Chemistry in Ancient Indian Science and Technology.]'' International Journal of Development Research Vol. 06, Issue, 12, pp.10784-10788, December, 2016</ref>  

Ancient India's contribution to science and technology include principles of chemistry which did not remain abstract but found expression in practical activities like fermentation processes, distillation of perfumes, aromatic liquids, manufacturing of dyes and pigments and extraction of sugar, extraction of oil from oilseeds, and metallurgy which has remained an activity central to all civilizations from the earliest ages. Archaeologists' findings of the Indus valley civilization showed a well developed urban system with public baths, streets, granaries, temples, houses with baked bricks, mass production of pottery and even a script of their own which depicted the story of early chemistry.<ref name=":0">Purwar, Chhavi. ''[https://www.journalijdr.com/sites/default/files/issue-pdf/7278.pdf Significant Contribution of Chemistry in Ancient Indian Science and Technology.]'' International Journal of Development Research Vol. 06, Issue, 12, pp.10784-10788, December, 2016</ref>  

In pottery making chemical processes were carried out in which materials were mixed, fired and moulded to achieve their objective. In the Rajasthan desert many pottery pieces of different shapes, sizes and colours were found. At Mohenjo Daro it was found that for the construction of a well, gypsum cement had been used which contained clay, lime, sand and traces of Calcium Carbonate (CaCO3) and was light grey in colour. Burnt bricks were manufactured on a large scale for making houses drains, boundary walls, public bath etc. Many useful products invented were plasters, hair washes, medicinal preparations etc. which had a number of minerals in them and were used by Indus Valley people.

In pottery making chemical processes were carried out in which materials were mixed, fired and moulded to achieve their objective. In the Rajasthan desert many pottery pieces of different shapes, sizes and colours were found. At MohenjoDaro it was found that for the construction of a well, gypsum cement had been used which contained clay, lime, sand and traces of Calcium Carbonate (CaCO3) and was light grey in colour. Burnt bricks were manufactured on a large scale for making houses drains, boundary walls, public bath etc. Many useful products invented were plasters, hair washes, medicinal preparations etc. which had a number of minerals in them and were used by Indus Valley people.

Copper utensils, iron, seals, gold and silver ornaments, and terracotta discs and painted grey ware pottery have all been found in thirty five archaeological sites in North India. Scientific dating of these artifacts corresponds to the non-aryan invasion model of Indian antiquity.<ref name=":0" />

Copper utensils, iron, seals, gold and silver ornaments, and terracotta discs and painted grey ware pottery have all been found in thirty five archaeological sites in North India. Scientific dating of these artifacts corresponds to the non-aryan invasion model of Indian antiquity.<ref name=":0" />

According to Samkhya, atoms (Anu-s) of these grosses elements are composite units made up of infra-atomic particles, the tanmatras. The chemical theory of the Nyaya-Vaiseshika system involves the theory of Anu-s or atoms comparable to the tanmatras of the Samkhya philosophy. The Samkhya virtually substantizes the “gunas”; the Vaiseshikas take them to be qualities which are always found in some dravya. According to Maharshi Kanada, every material of this universe is made up of kana or parmanu (atom) which are invisible, indivisible, eternal and indestructible. There are two states of anu- a state of motion and a state of absolute rest.     

According to Samkhya, atoms (Anu-s) of these grosses elements are composite units made up of infra-atomic particles, the tanmatras. The chemical theory of the Nyaya-Vaiseshika system involves the theory of Anu-s or atoms comparable to the tanmatras of the Samkhya philosophy. The Samkhya virtually substantizes the “gunas”; the Vaiseshikas take them to be qualities which are always found in some dravya. According to Maharshi Kanada, every material of this universe is made up of kana or parmanu (atom) which are invisible, indivisible, eternal and indestructible. There are two states of anu- a state of motion and a state of absolute rest.     

  The Vaiseshika sutras<ref name=":3">Gupta, B. (2012). ''An introduction to Indian philosophy: Perspectives on Reality, Knowledge, and Freedom''. Routledge.</ref>, define and explain the nature of dravya or substance, and classifies all dravyas or things of the world into nine: Earth, water, fire, air, ether/space, time, space, soul and manas (mind).

  The Vaiseshika sutras<ref name=":3">Gupta, B. (2012). ''An introduction to Indian philosophy: Perspectives on Reality, Knowledge, and Freedom''. Routledge.</ref>, define and explain the nature of dravya or substance, and classifies all dravyas or things of the world into nine: Earth, water, fire, air, ether/space, time, space, atman and manas (mind).

Each of the first five substances possess a unique quality, which makes the substance what it is. Maharshi Kanada recognized four kinds of atoms each having a unique quality or guna   

Each of the first five substances possess a unique quality, which makes the substance what it is. Maharshi Kanada recognized four kinds of atoms each having a unique quality or guna<ref name=":1" /><ref name=":5">Narayan, R. (2007). ''Nyaya-Vaisheshika: The Indian Tradition of Physics''. <nowiki>https://www.researchgate.net/publication/1880033</nowiki></ref>    

# kshiti or earth - smell   

# kshiti or earth - smell   

# vayu or air - touch   

# vayu or air - touch   

The first four are knowable by outer perception. The substances of earth, water, fire, and air are eternal and non-eternal. The atoms of these four substances are partless and eternal, because as partless they can neither be produced nor destroyed. The fifth substance, akasha or ether, has the characteristic of sound and is indivisible, eternal, and non-perceptible.<ref name=":3" /> Akasa (ether), according to Kanada, has no atomic structure; it is inert and ubiquitous serving only as the substratum of sound which is supposed to travel in the form of waves in the manifesting medium of vayu (air). Atoms are the primordial infinitesimal particles of everything except space or Akasha. Each atom has its individual characteristics, and it combines with other atoms to form the larger entities similar to molecules. These atoms are characterized by their characteristic mass, basic molecular structure such as dyad, triad, etc, fluidity (or it’s opposite), viscosity (or its opposite), velocity (or quantity of impressed motion- Vega) and other characteristic potential color, taste, smell or touch not produced by chemical operation. It is these four kinds of atoms involved in all chemical reactions while the space remains unaffected.<ref name=":3" />   

The first four are knowable by outer perception. The substances of earth, water, fire, and air are eternal and non-eternal. The atoms of these four substances are partless and eternal, because as partless they can neither be produced nor destroyed. The fifth substance, akasha or ether, has the characteristic of sound and is indivisible, eternal, and non-perceptible.<ref name=":3" /> Akasa (ether), according to Kanada, has no atomic structure; it is inert and ubiquitous serving only as the substratum of sound which is supposed to travel in the form of waves in the manifesting medium of vayu (air).<ref name=":1" /> Atoms are the primordial infinitesimal particles of everything except space or Akasha. Each atom has its individual characteristics, and it combines with other atoms to form the larger entities similar to molecules. These atoms are characterized by their characteristic mass, number, quantity, basic molecular structure such as dyad, triad, etc, fluidity (or it’s opposite), viscosity (or its opposite), velocity (or quantity of impressed motion- Vega), elasticity, gravity, and other characteristic potential color, taste, smell or touch not produced by chemical operation. It is these four kinds of atoms involved in all chemical reactions while the space remains unaffected.<ref name=":3" /><ref name=":1" />   

That matter is ultimately made of indivisible building blocks, thus appeared in India as part of philosophical school of thought long before Western inventions.     

That matter is ultimately made of indivisible building blocks, thus appeared in India as part of philosophical school of thought long before Western inventions.     

==== Combination of Atoms ====

==== Combination of Atoms ====

Atoms may conjoin or disjoin in reactions.<ref name=":3" /> The atoms combine driven by an inherent tendency which is their natural property to form dyads according to Prashastapada and three dyads combine to form a triad, whereas Maharshi Kanada maintained that different atoms combine in different patterns, some in pairs, some in triads, tetrads etc.   

Atoms may conjoin or disjoin in reactions. The atoms of the same bhuta (element) combine driven by an inherent tendency which is their natural property to form dyads according to Prashastapada. It represents the formation of binary molecules of elementary substances according to our modern conception. These binary molecules or dyads then combine among themselves by groups of three, four, five, etc., to produce larger aggregates in obedience to the moral law underlying the creation.<ref name=":1" /> Maharshi Kanada maintained that different atoms combine in different patterns, some in pairs, some in triads, tetrads etc.   

Therefore, Prashastapada's Basic unit of n dyads ≡ 1 dyad + 1 dyad… n dyads where n ≥ 1  

Therefore, Prashastapada's Basic unit of n dyads ≡ 1 dyad + 1 dyad… n dyads where n ≥ 1  

While Kanada's Atoms combine ≡ basic unit /molecule with two, three or n number of units  

While Kanada's Atoms combine ≡ basic unit /molecule with two, three or n number of units<ref name=":5" />

 

==== Effect of Heat ====

==== Effect of Heat ====

A substance may change qualitatively under the influence of heat in its course of existence. The Vaisheshika’s stand on such a change is that with application of heat a substance decomposes into paramanus or the basic unit with zero mass (not the unit of dyad, triad etc) followed by recombination of paramanus with a new basic unit arrangement and order resulting in a new substance. The Vaisheshikas hold that under the influence of heat, substances are broken down to the most basic entity (paramanu) before being transformed in to a new substance whereas the Nyaya school does not believe in decomposition in to the very basic entity.<ref name=":3" />  

A substance may change qualitatively under the influence of heat in its course of existence. The Vaisheshika’s stand on such a change is that with application of heat a substance<ref name=":1" />

 

- decomposes into original homogenous paramanus or the basic unit with zero mass (not the unit of dyad, triad etc)  

 

 

- recombination of paramanus with a new basic unit arrangement and order resulting in a new substance.  

 

The Vaisheshikas hold that under the influence of heat, substances are broken down to the most basic entity (paramanu) before being transformed in to a new substance whereas the Nyaya school does not believe in decomposition in to the very basic entity.<ref name=":3" />

 

 

 

A nature (Tattva) of the particular substance when it turns into another nature is called transmutation (Utparivartana) in scientific terms. A study on the Changes (Parivartana) and analysis (Visleṣaṇa) of the substance because of its origin and qualities is called Chemical Science of the particular substance. The Change is of two kinds such as   

A nature (Tattva) of the particular substance when it turns into another nature is called transmutation (Utparivartana) in scientific terms. A study on the Changes (Parivartana) and analysis (Visleṣaṇa) of the substance because of its origin and qualities is called Chemical Science of the particular substance. The Change is of two kinds such as   

2) Chemical Change (Rāsāyanika Parivartana)  

2) Chemical Change (Rāsāyanika Parivartana)  

The first type of change i.e. the Physical Change, is when the nature of the substance undergoes changes due to various reasons for a particular period of time and returns back to its previous state. For example, a piece of Iron forms into magnet after a deep friction (Gharṣaṇa) on the magnet and returns into being a piece of iron after it loses the magnetic effect. In same manner, water turns into ice at the state of high cooling (Himānka) and returns to liquid state after melting. In second type of change i.e. Chemical Change once the nature of the substance changes it cannot be reversed. For example, Milk turns into curd, and iron turns into rust etc.<ref>Jena, D. (2021). Concept of chemical science in Vedic literature. ''International Journal of Trend in Scientific Research and Development'', ''5''(4), 43. <nowiki>https://www.ijtsrd.com/papers/ijtsrd41144.pdf</nowiki></ref>  

The first type of change i.e. the Physical Change, is when the nature of the substance undergoes changes due to various reasons for a particular period of time and returns back to its previous state. For example, a piece of Iron forms into magnet after a deep friction (Gharṣaṇa) on the magnet and returns into being a piece of iron after it loses the magnetic effect. In same manner, water turns into ice at the state of high cooling (Himānka) and returns to liquid state after melting. In second type of change i.e. Chemical Change once the nature of the substance changes it cannot be reversed. For example, Milk turns into curd, and iron turns into rust etc.<ref name=":6">Jena, D. (2021). Concept of chemical science in Vedic literature. ''International Journal of Trend in Scientific Research and Development'', ''5''(4), 43. <nowiki>https://www.ijtsrd.com/papers/ijtsrd41144.pdf</nowiki></ref>  

=== Yantras ===

=== Yantras ===

The industries which sustained on chemical process may be classified broadly under the following headings.<ref>Danino. Michel, [https://www.academia.edu/23305766/Technology_in_Ancient_India_-_Michel_Danino Technology in Ancient India]</ref>

The industries which sustained on chemical process may be classified broadly under the following headings.<ref>Danino. Michel, [https://www.academia.edu/23305766/Technology_in_Ancient_India_-_Michel_Danino Technology in Ancient India]</ref>

# Ayurvedic Preparations: medical preparations including purificatory processes of mercurial compounds involved chemical reactions and apparatuses are discussed in [[Rasashastra (रसशास्त्रम्)|Rasashastra]] and [[Rasayana (रसायनम्)|Rasayana]].

# Ayurvedic Preparations: medical preparations including purificatory processes of mercurial compounds involved chemical reactions and apparatuses are discussed in [[Rasashastra (रसशास्त्रम्)|Rasashastra]] and [[Rasayana (रसायनम्)|Rasayana]].

# Pottery: Involves prolonged heating, fusion, evaporation, and treatment of minerals and pigments.

# [[Mineralogy (धातुशास्त्रम्)]] or the study of Minerals, broadly involves mining of Metal Ores such as those of Gold, silver, copper, lead, tin, zinc and iron and preparation of alloys such as bronze, and brass.

## Pottery: Involves prolonged heating, fusion, evaporation, and treatment of minerals and pigments.

# [[Textile Technology (तन्तुकार्यम्)]]‎‎

## Bead and Glass making: Glass is a solid fused mixture of lime, alkali, sand and metallic oxides. They were coloured by adding colouring agents like metal oxides. The Ramayana, Kautilya's Arthashastra, Brihatsamhita mention glass being used. Evidences of glass slag and glazing are found in Hastinapur, Takshila, Nevasa Kolhapur, Maheshwar and Paunar.<ref name=":0" />

# Building materials: Mortar and Cement using limestone, gypsum and their modified forms

## Jewellery making

# Fermentation Technology

## Dyeing: Numerous dyes from vegetable and mineral sources, use of mordants for textiles, craft paints which are relevant both in [[Textile Technology (तन्तुकार्यम्)|textile industry]] and [[Chitrakarma (चित्रकर्म)|chitrakarma]] or art of painting.

# Extraction of Oils:  Perfumes for cosmetics and consumption

# [[Chitrakarma (चित्रकर्म)]] or the art of painting used a variety of chemicals, mordants and pigments from vegetable and mineral sources.

# Dyeing: Numerous dyes from vegetable and mineral sources, use of mordants for textiles, craft paints

## Building materials: Mortar and Cement using limestone, gypsum and their modified forms

## Tanning of leather

# [[Mineralogy (धातुशास्त्रम्)]] or the study of Minerals, broadly involves mining of metal ores such as those of gold, silver, copper, lead, tin, zinc and iron and preparation of alloys such as bronze, and brass. A very comprehensive account of ores, minerals and metals with their extraction and working, their alloys is found in the Arthashastra. There was wide usage of metals for ornaments, utensils, warfare weaponry, coinage, and preparation of medicines.

 

=== Origin of Paints ===

=== Dyes and Paints ===

Pottery and pottery-painting were practised in India ever since the dawn of civilisation. In archaeological parlance, pottery is regarded as index to culture; an alphabet to history. Generally it is studied typologically, a correlation with others, rather than extensive technological analysis. However technological details such as - composition of clay, tempering agents, nature and components of the slips or glaze, nature of firing, porosity test and different chemical analyses - stand witness to not only the technological advancement of that culture but throws light on social, cultural, religious, economic, political aspects of that culture. Pottery both of fine and coarse types found in excavation sites of the Indian sub-continent are of many varieties, such as Red Ware, Buff Ware, Gray Ware, Black and Red Ware etc., broadly classified based on their colours.

Pottery and pottery-painting were practised in India ever since the dawn of civilisation. In archaeological parlance, pottery is regarded as index to culture; an alphabet to history. Generally it is studied typologically, a correlation with others, rather than extensive technological analysis. However technological details such as - composition of clay, tempering agents, nature and components of the slips or glaze, nature of firing, porosity test and different chemical analyses - stand witness to not only the technological advancement of that culture but throws light on social, cultural, religious, economic, political aspects of that culture. Pottery both of fine and coarse types found in excavation sites of the Indian sub-continent are of many varieties, such as Red Ware, Buff Ware, Gray Ware, Black and Red Ware etc., broadly classified based on their colours.

It is evident that methods like filtration, decantation, making pastes by rubbing on granite with little water, boiling with ingredients like calcium, catechu, soda etc, plant identification and collection of barks and leaves, and fermentation using rice starch were the adopted chemical processing techniques in preparation of pigments.<ref name=":12" />

It is evident that methods like filtration, decantation, making pastes by rubbing on granite with little water, boiling with ingredients like calcium, catechu, soda etc, plant identification and collection of barks and leaves, and fermentation using rice starch were the adopted chemical processing techniques in preparation of pigments.<ref name=":12" />

==== Tinted Glass ====

==== Glass Industry ====

Manufacture of glass and coloured glass is well documented in ancient literature such as Ramayana (2.90.27) (and other Buddhist texts), even though no glass objects have been recovered from Indus valley areas. Kautilya in his Arthashastra while laying down rules for the Superintendent of the treasury talks about the identification of various kinds of gems and precious stones and mentions a few times about glass; in the context of testing gems to place them in jewelry, in trade and tax payments, robbery and fines.<ref>Krishnamurthy. Radha, (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D.'' New Delhi: Indian National Science Academy. (Chapter Dyes, Mordants and Pigments: Page 312)</ref>

Manufacture of glass and coloured glass is well documented in ancient literature such as Ramayana (2.90.27), Mahabharata and ancient poetic works even though no glass objects have been recovered from Indus valley areas. Kautilya in his Arthashastra while laying down rules for the Superintendent of the treasury talks about the identification of various kinds of gems and precious stones and mentions a few times about glass; in the context of testing gems to place them in jewelry, in trade and tax payments, robbery and fines.<ref>Krishnamurthy. Radha, (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D.'' New Delhi: Indian National Science Academy. (Chapter Dyes, Mordants and Pigments: Page 312)</ref>

* शेषाः काच-मणयः ।। ०२.११.३६ ।। (Arth. Shas. 2.11.36)<ref>Arthashastra ([https://sa.wikisource.org/wiki/%E0%A4%85%E0%A4%B0%E0%A5%8D%E0%A4%A5%E0%A4%B6%E0%A4%BE%E0%A4%B8%E0%A5%8D%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AE%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A4%BF%E0%A4%95%E0%A4%B0%E0%A4%A3%E0%A4%AE%E0%A5%8D_%E0%A5%A8/%E0%A4%85%E0%A4%A7%E0%A Adhikarana 2 Adhyaya 11])</ref> rest are the glass gems.  

* शेषाः काच-मणयः ।। ०२.११.३६ ।। (Arth. Shas. 2.11.36)<ref>Arthashastra ([https://sa.wikisource.org/wiki/%E0%A4%85%E0%A4%B0%E0%A5%8D%E0%A4%A5%E0%A4%B6%E0%A4%BE%E0%A4%B8%E0%A5%8D%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AE%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A4%BF%E0%A4%95%E0%A4%B0%E0%A4%A3%E0%A4%AE%E0%A5%8D_%E0%A5%A8/%E0%A4%85%E0%A4%A7%E0%A Adhikarana 2 Adhyaya 11])</ref> rest are the glass gems.  

* क्षेपणः काच-अर्पण-आदीनि ।। ०२.१३.३८ ।। (Arth. Shas. 2.13.38)<ref>Arthashastra ([https://sa.wikisource.org/wiki/%E0%A4%85%E0%A4%B0%E0%A5%8D%E0%A4%A5%E0%A4%B6%E0%A4%BE%E0%A4%B8%E0%A5%8D%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AE%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A4%BF%E0%A4%95%E0%A4%B0%E0%A4%A3%E0%A4%AE%E0%A5%8D_%E0%A5%A8/%E0%A4%85%E0%A4%A7%E0%A Adhikarana 2 Adhyaya 13])</ref> Kshepana, guna, and kshudra ate three kinds of ornamental work. Setting jewels (kácha, glass bead) in gold is termed kshepana.<ref>Shamasastry. R, ''Kautilya's Arthashastra with English Translation'' (Page 120)</ref>

* क्षेपणः काच-अर्पण-आदीनि ।। ०२.१३.३८ ।। (Arth. Shas. 2.13.38)<ref>Arthashastra ([https://sa.wikisource.org/wiki/%E0%A4%85%E0%A4%B0%E0%A5%8D%E0%A4%A5%E0%A4%B6%E0%A4%BE%E0%A4%B8%E0%A5%8D%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AE%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A4%BF%E0%A4%95%E0%A4%B0%E0%A4%A3%E0%A4%AE%E0%A5%8D_%E0%A5%A8/%E0%A4%85%E0%A4%A7%E0%A Adhikarana 2 Adhyaya 13])</ref> Kshepana, guna, and kshudra ate three kinds of ornamental work. Setting jewels (kácha, glass bead) in gold is termed kshepana.<ref>Shamasastry. R, ''Kautilya's Arthashastra with English Translation'' (Page 120)</ref>

* Evidence of trade of glass items<ref>Shamasastry. R, ''Kautilya's Arthashastra with English Translation'' (Page 343)</ref>

* Evidence of trade of glass items<ref>Shamasastry. R, ''Kautilya's Arthashastra with English Translation'' (Page 343)</ref>

Archaeological evidences support the use of glass beads, bangles, jars, tiles etc. made from 6th or 5th century' B.C. onwards. Most of the glass objects were coloured. Glass manufacture practiced as an indigenous industry in ancient India is seen in excavations particularly in the south (Arikamedu, Uraiyur). Along with this, the technique of colouring glass also developed. The glass specimens show that the glass makers of ancient India were highly competent in giving different colours and shades to glass objects.  

Glass (kacha) was differentiated from crystal (sphatika) as early as in the days of Susruta (Chap. 46). Archaeological evidences support the use of glass beads, bangles, jars, tiles etc. made from 6th or 5th century' B.C. onwards. Most of the glass objects were coloured. Glass manufacture practiced as an indigenous industry in ancient India is seen in excavations particularly in the south (Arikamedu, Uraiyur). Along with this, the technique of colouring glass also developed. The glass specimens show that the glass makers of ancient India were highly competent in giving different colours and shades to glass objects.  

Chemical analysis revealed, just like in the case of pottery, that colouring agents were obtained from the metallic ores. Different chemicals added to them finally led to attribute different shades of colours and glazes to the glass objects. Coloured glass was prepared by mixing silicates of soda, lime and appropriate metallic oxides<ref>Jaggi, O.P. (1977) ''Science and Technology in Ancient India, New Delhi. Vol I'', p.203</ref>. Copper oxide, iron oxide, manganese oxides were generally used to give colours to the glass articles as for pottery. A special type of glass beads of 350 A.D. to 750 A.D. found at Ahicchatra is of gold foil glass. Layers of gold foils were poured in between two glass layers. All these prove that craftsmen in ancient India were highly skillful in the sophisticated technique of using metallic ores and chemicals as pigments in colouring very high temperature melting media like glass.

Chemical analysis revealed, just like in the case of pottery, that colouring agents were obtained from the metallic ores. Different chemicals added to them finally led to attribute different shades of colours and glazes to the glass objects. Coloured glass was prepared by mixing silicates of soda, lime and appropriate metallic oxides<ref>Jaggi, O.P. (1977) ''Science and Technology in Ancient India, New Delhi. Vol I'', p.203</ref>. Copper oxide, iron oxide, manganese oxides were generally used to give colours to the glass articles as for pottery. A special type of glass beads of 350 A.D. to 750 A.D. found at Ahicchatra is of gold foil glass. Layers of gold foils were poured in between two glass layers. All these prove that craftsmen in ancient India were highly skillful in the sophisticated technique of using metallic ores and chemicals as pigments in colouring very high temperature melting media like glass.

== Fermentation Technology ==

== Fermentation Technology ==

Fermentation is a particular method of digesting of relected substances that leads to chemical transformation of organic substances into simpler compounds by the action of fement.<ref>Mira Roy. (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D. by A. K. Bag.'' New Delhi: Indian National Science Academy. (Chapter Fermentation Technology : Page 437)</ref>

Fermentation is a particular method of digesting of relected substances that leads to chemical transformation of organic substances into simpler compounds by the action of fement.<ref name=":7">Mira Roy. (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D. by A. K. Bag.'' New Delhi: Indian National Science Academy. (Chapter Fermentation Technology : Page 437)</ref>

Generally fermentation quickly sets in substances of high sugar-content. Hence fermentation technology started in different parts of the old world with sweet-substances, be it vegetable or animal product. In Egypt honey was utilized first for preparation of intoxicating drink by fermentation. In Bharat, Soma juice, a sweet substance formed the first article of fermentation by the Vedic people. Although the technique or art of fermentation has been "self generated", the process may have been observed and used in remote past.

Generally fermentation quickly sets in substances of high sugar-content. Hence fermentation technology started in different parts of the old world with sweet-substances, be it vegetable or animal product. In Egypt honey was utilized first for preparation of intoxicating drink by fermentation. In Bharat, Soma juice, a sweet substance formed the first article of fermentation by the Vedic people. Although the technique or art of fermentation has been "self generated", the process may have been observed and used in remote past.

Milk products, like, curd (dadhi) requiring fermentation for changing of milk into such coagulated substance, was a very popular food article even in the Rigveda. The technique of curdling milk occurs in a number of texts connected with the Yajurveda. In the rituals Soma juice preparation involved preparing a sweet concoction for divine offering; while "sura" was another noted fermented product (a product of cereal and honey).

Milk products, like, curd (dadhi) requiring fermentation for changing of milk into such coagulated substance, was a very popular food article even in the Rigveda. The technique of curdling milk occurs in a number of texts connected with the Yajurveda. In the rituals Soma juice preparation involved preparing a sweet concoction for divine offering; while "sura" was another noted fermented product (a product of cereal and honey).<ref name=":7" /> They were also used in dyeing, mixing and dissolving operations and for binding and distilling mercury. In Sushruta Samhita, alcoholic beverages were referred to as 'Khola.'<ref name=":0" />

 

 

 

Kinva or ferment is prepared from boiled or unboiled paste of masha (Phaseolus radiatus), rice and morata (Alangium salviifolium) and the like.

== References ==

== References ==

[[Category:Shastras]]

[[Category:Shastras]]

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