Natural tar
Explanation
The Great Bath at Mohenjodaro is a prominent public structure located in the Citadel area of the Indus Valley Civilization. It serves as a prime example of the advanced engineering and architectural skills of the Harappans, particularly regarding hydraulic structures.
Detailed Analysis:
- The floor of the Great Bath was constructed using burnt bricks set in gypsum mortar.
- To ensure the structure was completely watertight and to prevent seepage, a thick layer of natural tar (bitumen) was applied along the sides of the tank and beneath the floor.
- This use of bitumen represents one of the earliest known examples of waterproofing in the ancient world.
- While gypsum was used in the mortar, the specific agent responsible for the water-tightness was the coating of natural tar.
Key Takeaway:
The Great Bath of Mohenjodaro utilized a layer of natural tar (bitumen) to ensure water-tightness, distinguishing it as a sophisticated feat of ancient hydraulic engineering.