By National Council of Science Museums
National Science Centre, New Delhi
Ancient Indians achieved great progress in alchemy (the older form of chemistry). Alchemical treatises of ancient India refer to various types of 'Yantras' or contraptions for different applications.
Ancient Indians achieved great progress in alchemy (the older form of chemistry). Earliest distillation of alcohol can be traced back to the archeological finds at Taxila. Ancient chemistry in India grew out of the early efforts to develop an elixir and to turn base metals into gold. Mercury and its elixirs were used in transmutation of the base metals into noble ones, as well as for purifying the body, rejuvenating it and taking it to an imperishable and immortal state. Out of the numerous alchemical texts, written between the ninth and the fourteenth century AD, some give alchemical ideas, while others are devoted to alchemy.
Rasashala DioramaNational Council of Science Museums
The second category includes Rasahrdayatantra by Govind Bhagwatpad, Srasaratnakara by Siddha Nityanatha, Rasarnava by an unknown author, Srasendracudamani by Somadeva, Rasaratnasamuccaya by Vagbhatta, Rasaprakasasudhakara by Yasodhara, Rasendracintamani by Dhundukanatha, Rasakaumudi by Sarvajnacandra, Rasabhesajakalpa by Surya Pandita, Rasasamketakalika by Camunda, Rasamuktavalina by Devanatha etc. There are several other works like Dhatukalpa, Dhatumanjari, Dhatumaranam, Rasgrantha, Rasakalpalata, Rasanibhandha, Suvaranatantra, whose authorships and dates have not yet been established.
Nagarjuna was the most prominent scholar in the field of Indian alchemy.
Rasashala, a typical alchemical laboratory of Nagarjuna is recreated in ‘Our Science & Technological Heritage of India’ gallery at National Science Centre, Delhi.
Swedani Yantra was used for continuous slow heating of ingredients.
Procedure: A pot with boiling water has its mouth covered with a piece of cloth and the substance to be steamed is placed on it, and a second pot is arranged in an inverted position over the rim of the first.
Patana Yantra was an apparatus used for sublimation and distillation.
Two vessels are adjusted so that the neck of the one fits into that of the other.
The junction of the necks is luted with a composition made of lime, raw sugar, rust of iron, and buffalo’s milk.
The Adhahpatan Yantra was a modification of the Patana yantram, an apparatus used for sublimation and distillation.
The bottom of the upper vessel is smeared with the substance, the vapour or essence thereof condensing into the water of the lower one. Heat is applied on the top of the upper vessel by means of the fire of dried cow-dung cakes.
This apparatus, Kosthi Yantra, was mainly used for extracting minerals.
This apparatus has a special furnace of angulas in width and one hasta (18”) in length and one hasta in height. Two Mushas (crucibles used in the laboratory) are taken, one of which has a lid with a hole.
The Musha with the lid is filled with ore and is fixed upside down on the furnace, surrounding the upper Musha is filled with hard charcoal made of Bamboo, Khadira, Madhuka and Badari wood.
A fire is lit in the charcoal and has to keep raging, by blowing air with the help of bellows. Gradually the essence of the mineral gets collected in the lower pot.
The Dola Yantra was mainly used for causing the chemical to perspire by exposing them to medicated steam.
In this yantram, a vessel filled with some liquid substance to half of its capacity is taken. Two holes are made opposite to each other near the mouth of the vessel.
A rod is then arranged through the two holes across the mouth. A bundle containing the material which is boiled is suspended into the liquid by tying it at the middle of the rod. Then the vessel is heated as required.
The apparatus is similar to fumigating apparatus.
Bars of iron are laid in a slanting position a little below the mouth of the lower vessel and gold- leaves are placed over them, and at the bottom of the vessel is deposited a mixture of sulphur, realgar, orpiment etc.
A second vessel, with its convexity turned upwards, covers the mouth of the lower one, and the rims are luted with clay. Heat is now applied from below. This is called fumigation of gold-leaves. Silver may also be similarly treated.
Taptkhal or Tapta Khalla Yantra was used for slow heating of Mercury.
The Tiryakpatan Yantra was used for purification of mercury.
Mercury is kept in a long vessel, with a bent tube at its neck. The lower end of the tube should be inserted into the body of another vessel containing water.
The mouth of these two vessels and joints are closed with clay and cloth etc. A blazing fire is placed under the first vessel.
The mercury falls into the water in the second vessel. Cold water is poured constantly on the second vessel to get sublimated mercury.
Mercurial products are generally processed through this apparatus.
Palika Yantra is a round shaped vessel with a bend vertical or horizontal arm to handle it. The apparatus is generally used in drawing out oil and small quantity of medicinal liquid.
It was used for sublimation of mercury. The substance is heated in lower pot and the upper one is kept cooled for deposition of sublimate.
This is an iron vessel placed in a cavity and subsequently filled with water. Another vessel is placed into this water with a small crucible containing mercurial products that are processed through Kacchapa Yantra.
It was used for addition of sulfur in different proportions in the mercury.
Gallery View, National Science Centre, DelhiNational Council of Science Museums
This online exhibition is created by National Science Centre, New Delhi, a unit of National Council of Science Museums, India
Bose D.M., Sen S.N. and Subbarayappa B.V. (Eds.): A Concise History of Science in India. Published for the National Commission for the Compilation of History of Sciences in India by Indian National Science Academy, 1971.