Proceedings of Indian Geotechnical Conference December 15-17, 2011, Kochi (Paper No. P-023)
ROCK ENGINEERING IN ANCIENT INDIA
A.S. Nene, Professor of Civil Engineering (Retd), VNIT Nagpur, Email: [email protected]
ABSTRACT: Sage Bhrugu grouped all ancient engineering and technological subjects into ten Shashtras (Engineering Sciences). These Shashtras, were further sub-divided into 32 techniques (Vidyas) and 64 skills /arts (Kalas). The paper presents status of rock engineering in ancient India. References related to rock engineering are available mainly in three Shashtras such as Surface transport, Dwellings and Forts and Castles. Tunnel construction was an important ancient art. Construction of huge temples, palaces and forts and dams involves use of stones. Information related to sources, classification, selection, and identification of defects in building stones, mortars for stone masonry and protective coats for stone idols etc are discussed in the paper.
INTRODUCTION White stones were considered best, followed by red, yellow For ages, stones are used for construction in different forms and black stones [2, 4]. The color of the stone should be for different purposes. During the ancient period in India, uniform. Stones, with different colors or different shades of stones were used in making sculptures and in making same color were considered unsuitable. The color variations blocks for building construction. in a stone are due to weathering of stones to different degree. Hence, such stones were considered unsuitable [2]. The strength and aesthetics of structures depends upon the Age - Based on age, stones were classified as child, young type of stone used in it. The beauty of Tajmahal lies more or old. The age of stone is mainly decided by the sound on the type of marble stone used for construction than the produced when it is hit with a sledge hammer. This is architecture of the building. classification is described below. Child- Sound Produced as by un-burnt bricks, shape -long or flat as a leaf [1, 3]. SOURCES FOR BUILDING STONES Young- Long ringing sound like bell, soft in touch, Stones are obtained from two sources namely, from hills with good smell, without pores [1, 2]. and from underground mines. The stones obtained from Old- Non-ringing sound, highly porous, highly hills (above ground) were considered better than those weathered [1, 2]. obtained from underground were. Stones obtained from The stones of first or third category are unsuitable for mines get softer when exposed to weathering agents such as construction [1, 2, 3]. rain, sunrays air etc. However, the stones obtained from Gender - Stones were classified as Male, Female, or hills were already exposed to weathering. Neutral. This type of classification is explained below. According to Kashyapashilpa [1] stones obtained only from Male- Big, rounded, produces sparks when hit hills, riverbanks and forests are suitable. The stones with chisel [1, 2, 3]. obtained from barren land, graveyard or those embedded in Female- Medium size, soft in touch, broad at base ground are unsuitable. Stones obtained from sites [1, 2, 3]. unsuitable for habitation are also unsuitable. Neutral- Small, broad at top, not sounding [2, 3].
The masculine stones (of high compressive strength) were CLASSIFICATION OF STONES used for columns and roofs, feminine stones (of high As per Kashyapshilpa [1], the stones were classified flexural strength) were used as beams and neutral gender according to its color, age and gender. stones are used as aggregates in foundations. Color - The basic four colors in the order of priority for selection were White, Red, Yellow and Black. Shades of DEFECTS IN BUILDING STONES each of these colors were quoted by examples as given The defects were described in details in many ancient texts. below. The defects are lines (streaks), spots and cracks. x White- Milk, Jaya flower, Buffalo’s eye, Conch, Moon, x Lines: The lines are of thee types, curvilinear (as Pearl Crystal etc. thread), straight (as sun rays) and parallel (as rains) x Red - Indragop (insect), Rabbit’s blood or x Spots: The spots can be of three types depending upon Pomegranate Flower etc. the size. Lemon fruit (35-40 mm), grape size (5-10 x Yellow - flowers like, Mallika or Korandi etc. mm), less than 5 mm. The spots were further grouped x Black- Kajal (eye ointment), Blue lotus, Wasp, Vest under three heads, brown (like iron ore), gray (like part of peacock, black gram etc. wasp) or black [1].
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A.S. Nene SELECTION OF BUILDING STONES Huge stones were intricately carved to fit together without In addition to the above-mentioned specifications, some concrete, mud, or mortar of any kind. Stones had 12-14 other guidelines are available in the ancient texts. These are sides. Some researchers claim to have identified the magic described below. plants called as ‘jotcha’ or ‘punco-punco’ (Ephedra The stones, which are weathered, contains sand andina). grains or disintegrates on immersion in water are termed unsuitable [1, 3]. Stones from unsuitable site, used stones, stones with inferior minerals are termed unsuitable [2, 4]. Stone, with one side very long compared to other sides should not be used. [3]. Brittle or porous stones, non-uniform colored stones are unsuitable [3, 4]. Stones with cavities inside or poisonous stones should not be used. The ancient texts describe methods to check such defects [2, 3]. Fig. 1-Stone wall at Cuzco (Peru) SUITABILITY OF BUILDING STONES The suitability of building stones was decided on the basis ADAMANTINE GLUES of color, lines, spots or other defects. White lines on stones The subject of preparation of adamantine glue was closely of any color are acceptable but any line on white colored connected with construction of temples. A bonding agent stone is not acceptable [1, 4]. The white lines are due to was very essential for fixing idols or in wall construction, quartz mineral, which is very hard, but lines of other colors when cement and other modern materials were unknown. are formed due soft minerals. The stones should not contain Even now, these glues were known as Astabandha, are any spots [1]. prepared in temple premises for fixing or re-fixing images of gods. Four such glues were described in ancient texts. The spots are due to soft mineral. “Black stones with white One formula or method is described below [5]. spots are sailable. But stones with black or green spots are unsuitable, [4]. The stones with excessive lines, spots and Table 1 shows the ingredients for adamantine glue. defects are unsuitable for construction [2]. Table 1- Ingredients Sn Sanskrit English/ Latin DETECTION OF DEFECTS IN ROCKS 1 Tinduka Fruits of Diospyros paniculata The stones, to be used for idol preparation were carefully 2 Kapittaka Feronia elephantum inspected. Microscopic defects, which are invisible to eyes, 3 Shalmali Flowers of silk cotton were detected by applying some herbal paints so that the 4 Sallaki Seeds of Boswellia serrata defects are clearly visible. Similar modern techniques are 5 Dhanavana Barks of Orris root used to detect faults in metal casting. An ancient procedure 6 Vacha Barks of Orris root for preparation of four herbal paints as described in 7 Shrivasaka A tree resin used as incense Mayamat [2] is given below. 8 Raktabola Myrrh 9 Guggulu Commiphora roxburghii 1. Mix and grind equal parts of Ativish, Hirakas and Geru 10 Bhallataka Semecarpus anacardium in milk, apply this paint to stone and allow to dry overnight. 11 Kunduruka Deodar tree resin 2. Mix and grind equal parts of Hirakas and Chor in milk 12 Atasi Linum usikatissimum and apply this paint to stone and dry for three days. 13 Bilvaphal Fruits of Aegle marmelos 3. Mix and grind equal parts of Jatamasi, Kusht, Gabha and
Ratree in decoction of Trifala, apply this paint to stone and Ingredients (1-6), in equal parts are boiled in 256 parts of dry for three days. water until the decoction reduces to an eighth of its original 4. Mix and grind equal parts of Jatamasi, Rog and volume (i.e. 32 Parts).
Ashwamari in rainwater mixed with milk, Apply one of above mentioned paint to stone and allow it to The sediments were mixed with other substances (7-13). dry for three days. Such paints were used to detect micro The resulting paste is termed as adamantine glue. This glue cracks or fissures. is heated and then used in construction of temples, mansions, walls and wells as well as fixing Siva’s emblems STONE SOFTENING and idols of gods. This mortar was expected to last for a
The modern Peruvians believe that the Incas employed million years. certain methods to make their stones fit so perfectly. They knew a plant whose juices rendered the surface of a block BREAKING OF STONE BLOCKS so soft that the intricate fittings were possible Fig. [1].
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Rock engineering in ancient india Brihat Samhita [6] contains information on procedure for were used. The oldest sculptures found in the two cities of breaking stone blocks so that it can be used as building Indus valley civilization; were Mohenjodaro and Harappa. stones. The principle involved in this process is "Heat and It dates back to 3000 BC. The Indus valley civilization cool ". Rock is a bad conductor of heat. When a preheated shows the use of tertiary limestone, sandstones and rock mass is cooled quickly the rock breaks, along its Mesozoic steatite for stone statuary. Vindhyan sandstones cleavage planes due to unequal expansion and contraction. were very extensively used for carving the statues. Kaimur Following methods are mentioned. and Bhandar sandstones remained the popular sculptural material in the greater part of northern India. Heating: A pyre of wooden logs of Palash or Tinduk trees heats the stone block. The heating is continued until the color of wooden logs becomes bright red or orange. Cooling: The fire is moved to adjacent area of rock surface. The preheated surface is quickly cooled down by pouring certain types of liquids listed below. x Solution of quick lime in cold water; x Solution prepared by mixing buttermilk with rice paste and ripe berries. x Solution prepared by boiling Neem leaves, some tree barks and fruits of Tinduk tree. This is diluted with cow's urine and cold water.
TEMPERING OR HARDENING OF TOOLS Specially prepared tools such as chisels, crowbars, pickaxe etc are necessary for breaking the stones. Brihat Samhita Fig. 2- Suranga-a water tunnel [6] describes some methods of tempering of iron tools. The three steps are as below, Rock cut architecture made its beginning in the third
x Heating the tool in fire until it becomes red hot. century BC and reached its acme in the land of Ajanta in
x Applications of pastes of certain materials and / or Sixth century AD. dipping the red-hot tool in a specific solution. x Sharpening the tools. India has been a land of arts and crafts. Various art forms The materials used in step two were excreta of pigeon and have evolved in metallic and non-metallic materials here. rat, powder of horns of a buffalo and milk extract of a Stonework was also one of such wonderful crafts. India has Mandar plant. In another method, a solution of buttermilk a rich tradition of stone craft. Guilds of masons and stone and ash of banana plant was used for cooling the red-hot carvers have existed here since the 7th century B.C. tool. Different types of stones like, marble, soapstone, sand stone were used by artisans in India. Stone craft in India was not SURANGA –WATER TUNNELS only restricted to ornate carvings on temples or sculptures Suranga is a tunnels bored horizontally on the slopes of of deities, but it was also used in making items like carved hills to get clean drinking quality water. Suranga is best panels, tiles, paper weights, pen stands, models of historical suited for the laterite soils because this type of soil does not buildings, sculptures of animals and humans etc. The basic collapse while digging. These `Surangas’ can be seen in design was traced on the stone and it is given a crude shape. many parts of Dakshina Kannada district of Karnataka and The final carving was then carried out and the items were Kasaragod district of Kerala Fig. [2]. polished.
Suranga digging is a craft mastered by local women. This Marble cutting achieved a remarkable level of requires patience and some knowledge of water flow. The sophistication, with the intricate undercutting in the 11th suranga is dug such a way that the seepage water is flown and 12th century temples at Mt-Abu approaching the level outside easily. ‘Quanat’ was a similar structure used in Iran, of filigree. The Tejo Mahal (Tajmahal) at Agra is perhaps Iraq and some other parts of Middle East for the purpose of the finest example of marble cutting in the world. water. The history of ‘Quanat’ goes beyond 700 B.C. CONCLUSIONS BUILDING STONES Based on limited information available in ancient texts, The Indian sub-continent’s architecture is well documented following conclusions can be made, by stone sculptures, which cover a period of more than five 1. Different types of stones were used in the ancient thousand years. Different types of stones were used in period for making sculptures, and as blocks for different periods. Stones were selected subject to the job making buildings. requirements. Transport being a cumbersome work, the 2. The stones were selected depending upon their locally available stones from the vicinity of the job site availability and the job requirement. Care was
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A.S. Nene taken in selection of the stones specifically looking into micro cracks, texture and strength. 3. The ancient Indian information on rock Appendix - Glossary of terms engineering is applicable even in modern times. Name Description 4. Modern methods of testing were not known in Amalaki ancient period and hence more information on Amala tree-Emblica officinali defects of rock was provided in ancient texts. Ashwamari Yellow Oleander Ativish Plant root-Linum usikatissimum REFERENCES Bibhitak behda tree -Terminalia bellirica The titles shown in italics are ancient engineering texts or Chor Indian wormwood -Davana Shilpasamhita. Gabha Sage herb -Salvia officinalis
1. Kashyapashilpa, Ed.by Vaze, Anandasrama Sanskrit Geru Red ochre Series No. 95.Pune. Haritaki Hirda tree-Terminalia chebula 2. Mayamat, Pub. By Saraswati Mahal Library Series Hirakas Ferrous sulphate No.113, Thanjavur (1968). Indragop 3. Shilpratna, Ed. Shrikumar, Pub. Gaikwad Oriental Ladybird -a kind of red beetle Series, Baroda. Jatamasi A herb- Nardostachyjatamasi 4. Vishnudharmottar Purana, Pub. By Khemraj Korandi Yellow flower- spiny barleria Shrikrishnadas, Mumbai. Kusht Alpina galangal-aromatic tuber
5. Shilparatnakar, Ed. by Trivedi, Published by Mallika Yellow Jasmine flower Chaukhamba Sanskrit Series, Gaya. Mandar 6. Brihat Samhita (of Varahamihir), Pub. By Khemraj Blue cedar tree Shrikrishnadas, Mumbai. Neem Neem tree- azadirachta indica Palash Tree-flame of forest Ratree Night-Blooming Jasmine Rog A herb
Tinduk Tendu tree-Diospyros paniculata
Trifala A mixture of 3 dry powdered fruits- Amalaki, Bibhitak and Haritaki
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