it gets red colour outside and black inside. Inside
of it turns dark because it does not get enough
oxygen to be burnt since it is filled with chaff. This
technology of burning clay pots disappeared after
300 B.C. In addition, there was the technology
of polishing and colouring the outside of the
clay pot after it was burnt. The best example for
this is the coloured clay pot discovered in the
ancient house in Udaranchamadama. It had a
white background with lines painted in orange
colour. The natural red colour brown stones had
been used to colour them. Before this clay pot
was made, clay was dissolved in water and kept
until the tiny particles were deposited. Next, very
clean clay particles, as alluvial was used to make
this clay pot. This method is very similar to the
one used at present day to make porcelain ware.
Since our people used earthenware abundantly in
ancient time, the technology, which was needed
to make them in a standard way, advanced from
the proto-historic era.
Activity 1Prepare an article for a newspaper on the title
scientific knowledge and the technical skills of
our ancestors referring to the lesson "the early
stages of Applied Science."
5.2 The Maturity of Scientific Usage
5.2.1 Water Management
Since the oldest settlements in our country had
distributed in the dry zone, the major challenge
that those people had to face was collecting
sufficient water for agricultural activities and
their day-to-day needs. The need of constructing
tanks, ponds and canals arose on this ground.
The term ‘water management’ is the most suitable
one to name any strategy used to gather water.
We can understand the nature of the marvellous
knowledge of our scientists and engineers who
lived in the ancient time by looking at activities
that they have done for water management.
Constructing large tanks – One of the great
activities in our historical age was making
large tanks. These large tanks were built based
on multiple-facts such as making agricultural
activities successful, controlling floods,
and meeting the needs of the urban people.
Constructing large scale tanks is a technical
attempt with a very complex scientific knowledge.
Some names of the large scale tanks constructed
during the Anuradhapura era have been given
below. After understanding their magnitude,
you will easily realize the fact that how much of
scientific knowledge is needed to construct and
maintain such tanks after they are filled with
water.Kawdulla Tank (2537 hectares)
Minneriya Tank (2550 hectares)
Hurulu Wewa (2125 hectares)
Kala Wewa (2125 hectares)
Padaviya Tank (2357 hectares)Major factors that should be paid attention in
constructing such large scale tanks are keeping
the gathered water for a long time by controlling
the pressure caused by its colossal capacity of
gathered water and controlling the power caused
by its extremely destructive pressure when the
water is taken out for use.Tank bund – It is essential to construct the tank
bund strongly if it needs to hold a huge water
capacity in it. When such a thing is practically
done, what is important is taking steps needed
to prevent the tank bund from sinking when
it is constructed. What our ancient engineers
had followed for this is that constructing the
tank bund on a naturally established rock. After
finding such a rock located between two natural
hills, the tank bund was built connecting the hills
from either side. As the tank bund is connected
to two natural hills, it provided some assistance
to the strength of the tank bund. The bund of
the ‘Yodha Wewa’ is about seven miles in length