A big dolmen with four petroglyphs that portray men with tridents and a wheel with spokes has been found at Kollur, near Tirukoilur, 35 km from Villupuram in the Indian state of Tamil Nadu state. The discovery was made by K.T. Gandhirajan, who specialises in art history, when he led a team to that area.
     What is special about the latest find is that while two men portrayed in the petroglyphs have tridents in their hands, a third is brandishing unidentified weapons. Unusually, these figures have been chiselled on the dolmen's capstone. While the prehistoric artist has provided a geometrical pattern to the two men with tridents and other weapons, he has chiselled the third man, with an ornament on his chest, in a free-flowing manner. This is the second time that a dolmen with petroglyphs has been found in Tamil Nadu. The earlier discovery in the Nilgiris district was also made by Mr. Gandhirajan. But it was a circular dolmen with a petroglyph on the slab wall.
     "The three figures belong to different periods. But the two men holding tridents are chronologically close to each other," Mr. Gandhirajan said. He estimated that while the dolmen itself was 2,500 years old, the petroglyphs might be about 2000 years old. The tridents could have been hunting or fishing weapons. Their depiction showed that the engravings date back to the Iron Age (circa 1000 BCE to 300 BCE). The engraving of a wheel was significant because the men who erected the dolmen had the knowledge of wheels.
     Six more dolmens were found nearby, on the banks of a lake at Kollur. In addition, three dolmens were situated on the bed of the lake which formed at a later period. Dolmens could have been used as shelters by tribals during rains or winter. Sometimes, dolmens had paintings of red ochre or white kaolin. "Hundreds of megalithic dolmens were once found in Tamil Nadu. Urban development and extension of agricultural land led to locals smashing them up or carting away the granite slabs for use in their houses. The Tamil Nadu Archaeology Department must make a survey of the surviving dolmens, and it should fence them. For these sites are directly connected with the pre-Sangam or Sangam age culture of Tamil Nadu," Mr. Gandhirajan said.

Source: The Hindu (20 September 2009)