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