ANCIENT INDIAN METALLURGY

Contents

• Introduction
• Crucibles
• Dating of Brhad-vimana-shastra Nineteenth Century
• Tortoise Furnace
• Air Blowers (Bellows)
• Preparation of Metal Powder
• Binders and Glues-l
• Binders and Glues-2
• Metallurgy – Metals for Aircraft
• Interesting Facts
• References

Introduction

Indian heritage in Gold, Silver, Bronze, Copper, Zinc and Iron and Steel is a celebrated one. Smelting of metals and derivation of alloys was done since 3000 BCE in ancient India. In the exchanges of goods between India, Egypt and Rome, metal trade from India was significant. Indian tools made from iron and steel were in great demand for war as well as agriculture.

Records show that the first supplies of the weapons that figure in the earliest recorded history of the people of Mediterranean came from India. As did Wootz steel, from which the famous Damascus blades were made. In fact, ‘Wootz’ derived its name from the Kannada word ‘ukku’ meaning crucible steel. Literary accounts suggest that steel from southern part of Indian subcontinent was exported to Europe, China, and countries of the Middle East.

The most outstanding examples of the capability and workmanship of Indian artisans include the famous Iron pillar at Delhi that stands rust-free even after some 1500 years, and the 1-ton, 2.1 meter high, 4^th century copper statue of Buddha that was found in Bihar and is now housed in a British museum. Yet another contribution of ancient India to metallurgy is the technology to produce pure zinc and high zinc-copper alloys.

These, along with hundreds of other beautiful sculptures and icons in bronze and copper, belonging to periods earlier than 2000 BCE, bear testimony to the technological excellence and consummate skill of early Indians in producing and shaping metals.

British records of the 18^th century show that the country had 20,000 furnaces operating across the country indicating the geographical spread of this knowledge.

Crucibles

Purvokta – bijalohanametasyameva varnitam

Uttamadhamamadhyapabhramsanam galanavidhau

Musassaptottaracatussatabheda itiritah II

Translated as – (The melting) of the aforesaid base metals is described here only. In the melting methodology, of good, coarse, average and pig metals, 407 varieties of crucibles are mentioned.

Tasarn dvadasavargah syurjatinirnayah kramat I

Translated as – In the order of origin, there are 12 groups in them.

Lohesu ye bijalohastesam galanakarmani II

Dvitiyavargoktaruusa eva srestha itiritah I

Translated as – In the melting of base metals, it is said, that the second group of crucibles is the best.

Etesarn galane musah pratyekarn vargatassmrtah I

Tesu dvitlyavargasthamusabheda

maharsibhih II

Catvarirnsaditi prokta musakalpa yathakramam I

Tasu ya pancarrutyukta musantarmukhanamika II

Galane bijalohanarn suprasasta itiritah II

Translated as – In the melting of these (base metals), crucibles are remembered from each class of these. The crucible varieties in the second category is mentioned as forty, in order, by the great sages, in (the work) Musha-kalpa.

Amongst these, the one that is mentioned as the fifth named Antar-mukha (inward reflecting) is said to be the best in the melting of base metals.

Source

Brhad-vimana-shastra, Musadhikaranam, Slokah 54-56, 58-60, Maharsih Bharadwaja (Post Vedic Period)

Dating of Brhad-vimana-shastra Nineteenth Century

Brhad-vimana-shastra (BVS) came into being in the modern times as a revealed text, the revelation having occurred through one Mr. Anekal Subharaya Shastry (born in 1866). An (unpublished) enquiry with the descendents of the family shows that Mr. Shastry had found the manuscript and attempted glory for himself by delivering it as a revelation. Swami Dayananda Saraswati (1824: 1888) in his A treatise on Rig-veda (1875) refers to Bharadwaja’s Vimana-shastra.

In the same year, a manuscript of the text had been discovered in a temple in India. Thus in the 19^th century, this work was certainly known.

Bharadwaja’s Vimana-shastra is considered a part of Yantra-sarwaswam – All about machines. This is one of the 40 sections that Yantra-sarwaswam is made of. One school of thought places Bharadwaja in 4^th century BCE. There are others who believe that Bharadwaja belonged to the Puranic period or earlier.

Tortoise Furnace

Kurmavyasatikamevamuktva sastranusaratah I

TatsvarfIpaparijfianarthamakararh sarnpracaksate II

Translated as – Having stated the Tortoise furnace, as per the scientific treatise, now let us study the shape and size, for further study.

Caturasrarh vartularh va kurmakararn yathavidhi I

Vitastidasakarn kundarn karayet bhuvi sobhanam II

Translated as – A square, circular or tortoise shaped pit of ten palms may be prepared nicely in the earth.

Bhastrikasthapanaya tu tatpurobhagatassphutarn

Kurrnangavat pancamukham pithamekarn

prakalpayet II

Translated as – For the installation of the air-blower, clear space may be marked on the front side. A tortoise like five-corned structure may be constructed.

Tatkundasyantarale tu musakundarn ca vartulam

Kalpayitva bahirbhage kundasyavaranadvayarn II

Translated as – Inside may be finished circular to take up crucible and outside the furnace two coats of plaster shall be provided.

Ingalapuranarthaya yathasastrarn prakarayet I

Parsvayorubhayostasya yantrasthapanarn kalpayet II

Translated as – For charging coal, two parts on each side may be provided and on the rear, metal pouring mechanism may be erected.

Samyaggalitalohanarn rasasarnpurane sudhih I

Racana kurmakundasya uktameva maharsibhih II

Translated as – Perfectly molten metals, in fully molten state are viscous, the furnace described by the saints here is to handle this in proper manner.

Source

Brhad-vimana-shastra, Slokah 77-83. Vyasatikadhikaranam, Maharsih Bharadwaja. (Post Vedic period).

Etymology

Kurrna-kunda : tortoise-furnace.

Air Blowers (Bellows)

Sarvesarn lohavarganam galanartharn visesatah

Dvatrimsaduttarapancasatarn bhastra itiritah II

Translated as – For melting all types of metals, there are five hundred and thirty two types of air blowers.

Tasam vargabhedastu astadha samprakirtitah I

Vargesvastamavargiyo bhastrikasu yathakrarnarn II

Nirnita kurmakundasya sodasi kurmabhast rika I

Sarvesarn bhastrikanarn tu racanakramanirnayah II

Translated as – They are divided into eight classes. Sixteenth in the eighth class is called Kurma-bhastrika (Tortoise air-blower) which is associated with Kurma-vyasatika (Tortoise furnace).

Bhastrikanibandhanakhyagranthe sarnyannirupitah I

Translated as – Construction details of all air-blowers are provided in the book, Bhastrika-nibandhana.

Source

Brhad-vimana-shastra, Slokah 91, 92, 93. Bhastrikadhikaranam, Maharsih Bharadwaja. (Post Vedic Period)

Preparation of Metal Powder

Retitarn ghrtasarnyuktarn ksiptvayah kharpare pacet I

Lauhe drsadi lauhafica mudgarena hatarn muhuh

Translated as – Throw flowing iron mixed with water in a broken pot and melt it.

Iron is beaten repeatedly in an iron mortar with a pestle.

Atha svarnam pesanartharn patnkrtya yathamrdu II

Tatpatrarn sakalikrtya suksmatsuksmatararn punah I

Kificitsikatasarnmisram suddhatoyavimisritam I

Pesayet pesanisvabhre suslaksnadrsada sudhih I

Translated as – A wise person, for grinding, after making the gold into soft leaves, after making the leaves into finer than finer fragments, mixing it with sand and clean water, grinds the ground gold, in a grinder with a very soft pestle.

late supiste tatpiste kacapatre jalaih saha I

Alodyordhvagatarn pankarn sikatarn ca punah

punah I

Santyajya jatarn svarnasya pankarnatyujjvalarn

budhah II

Translated as – When the mixture is ground finely, knowledgeable people, stirring the mixture with water in a glass vessel, filtering and discarding repeatedly the slurry of sand that comes up, get the highly shining slurry of gold.

Source

Rasa-ratna-samuccayah, Chapter 5, Slokah 106, Vagbhatah (12^th  Century AD)

Rasendra-sara-sangrahah (9^th Century AD) Silpa-ratnam, Chapter 46, Slokah 124-128 (11^th  Century AD).

Notes

Grind the ground gold would mean to grind repeatedly.

Binders and Glues-l

Amarn tindukamamarn kapitthakarn

puspamapi ca salmalyah I

Bljani sallakinam dhanvanavalko vaca ceti II

Translated as – Take unripe tinduka, unripe wood-apple, flower of silk cotton, seeds of sallaki, bark of dhanvana and the vaca root.

Etaijli saliladronah

kvathayitavyosstabhagasesasca I

Avataryossya ca kalko dravyairetaih

samanuyojyah II

Translated as – These materials mixed in a bucketful of water should be boiled till it (the mixture) is reduced to one eighth in volume. This residue should be mixed with the following materials.

Srivasakarasaguggulubhallatakakunduru-

kasarjarasaih I Atasibilvaisca yutah kalkosyam vajralepakhyah II

Translated as – Turpentine, guggula resin, resin of bhallataka, jasmine, sarja, linseed and vilvam. This mixture is called Vajra-lepa.

Source

Brhat-samhita, Varahamihira (6^th  century AD)

Notes

Varahamihira’s Brhat-samhita describes Vajra-lepa and Vajra-sanghata. The Ashoka Pillar is basically a sand-stone pillar coated with Vajra-Sanghata to look like a metal pillar. Mauryan caves in Bihar also have a coating that gives the surface the look of glass.

S.No	Sanskrit name	Common Terminology	Botanical name
1	Tinduka		Diospyros paniculata
2	Kapitthaka	Wood apple	Feronia elephantum
3	Shalmali	Silk cotton	Morus acedosa
4	Sallaki		Bosewellia		serrata
5	Dhanvana		Dhanvana
6	Vaca	Orris root	Vaca
7	Shrivasaka	Turpentine	Myrrh
8	Guggula		Commiphora roxburghu
9	Bhallataka		Semecarpus anacardium
10	Kunduruka	Jasmine	Cunduru
11	Sarja		Resin
12	Atasi	Linseed	Linum	usikatissimum
13	Bilva	Vilva	Aegle marmelos

 

Binders and Glues-2

Gomahisajavisanaih khurarornna

mahisacarmagavyaisca I

Nimbakapittharasaih saha vajratalo nama

kalko nyah II

Translated as – With the horn, hoof and mane of cow, buffaloes and goat and with the hide of buffaloes and cow along with the juice of neem and wood apple another paste called Vajra-tala (is produced).

PrasadaharmyavaJabhiliilgapratimasu kudyakupesu I

Santapto datavyo varsasahasrayutasthayi II

Translated as – The ten thousand year enduring heated (paste) should be given in (the construction of) palaces, mansions, roofs, lingas, idols, walls and wells.

Astau sisakabhagah karnsasya dvau tu ritikabhagah I

Mayakathito yogosyam vijiieyo

vajrasanghatah II

Translated as – Taking 8 parts of lead, 2 parts of bell metal, and 2 parts of the calx of brass, this mixture is called Vajra-sanghata by Maya.

Source

Brhat-samhita, Varahamihira (6^th century AD)

Notes

Maya is a reference to Maya-matam authored by Kapila-Vatsyayana (6^th Century AD), who had named his work after the celestial Architect Maya.

Metallurgy – Metals for Aircraft

Atha vaimanikan lohananukramisyamah saumaka-

saundalika – maurtvikascaitat samrnelanadusmapah

sodasadha bhavantIti te

vaimanikah II

Translated as – Now we sequence the metals for aircrafts – Thermal (Saumakal, Acidic (Soundalika) and relating to shape (Maurtvika). The aircraft technologists say that by alloying these (three metal categories) 16 varieties of heat-conducting metals come into being.

Usnambharosnaposnahanardjamlatrdviranda

paftcaghnognitrd bharahanag§itahano

garalaghnamlahano visambhara-visalyakrd

dvijamitraSca vatamitragcetityadih II

Translated as – These are heat bearing, heat conducting (thermal), heat proof, shining, acid-proof, toxic (weapon grade) non-malleable, fire-proof, weight-proof, cold-proof, poison-proof (anti toxic), acid proof (alkaline), toxic (weapon grade), surgical grade, wrought metal and wind-proof.

Source

Brhad-vimana-shastra, Lohadhikaranam, Maharsih Bharadwaja (Post Vedic Period)

Etymology for technical words

Saumaka   = Of the moon = Cool = Relating to temperature = Thermal

Saundalika = Relating to juices/acids

Maurtvika = Concerned with shape/form.

Panca=ghna Non-malleable

Garala-ghna = Poison-proof = Anti-toxin

Usna-hana = Heat-proof

Bhara+hana = Weight-proof

Sita+hana = Cold-proof

Amla+hana = Acid-proof = Alkaline

Amla+trd = Acid-proof

Agni+trd = Fire-proof

Ghna, han, trd = mean to kill, quench.

The rest are based on positive attributes.

Usna+hana = Heat + bearing

Visam-bhara = Poison + bearing

= Toxic (weapon-grade)

Usnam+pa = Heat + protecting

= Heat conducting

Raja         = Shining = White

Vi+salya+krt = Special + Cut + Do = Surgical grade

Dvija-mitra = Twice born = Wrought metal

Vata- mitra =Wind + friend (wind-proof)

Interesting Facts 

You seem to have put on a little weight

What is the secret behind Delhi’s famous Iron Pillar that stands rust-free even after more than 1600 years? Metallurgists at the Indian Institute of Technology, Kanpur, have discovered that a thin layer of ‘misawite’, a compound of iron, oxygen and hydrogen, has protected the cast iron pillar from rust.

In a millennium and a half, it is calculated that this layer has grown to a thickness of 50 micron. The protective film was formed catalytically by the presence of high amounts of phosphorous in the iron -1 % as against less than 0.05% in today’s iron. The high phosphorous content is the result of the unique iron-making process practiced by ancient Indians, who reduced iron ore into steel in one step by mixing it with charcoal.

The pillar-over 7 meters high and weighing more than 6 tones – was originally erected outside a Vishnu temple during the Gupta dynasty’s rule in 320-540 AD.

• The Hindu (29/8/2002), Iron pillar and nano powder, B.G.Prakash. 11. 7

Zinc Distillation in Rajasthan

Europe learnt to produce zinc in 1746. In late 17^th century, zinc was imported in small quantities from the East and used in the production of brass. Before the advent of present-day high-pressure technology, zinc had to be produced as a vapor because of the vast difficulties in its distillation process. But, it was distilled in India more than 2,000 years earlier through the use of a highly sophisticated pyro-technology. Distillation of this metal in India was brought to light through a series of nearly intact structural remains of ancient Indian zinc distillation furnaces at Zawar near Udaipur in Rajasthan.

• Who remembers ancient India’s scientific wealth? Md.Yazeeruddin,  World Institute for Asian Studies, Vol.5 No.361 (19/04/2006).