Second colonial lighthouse, Chennai

 2nd lighthouse 1834. www.destinationinfinity.org

1892 old lighthouse and a new one on HC tower. www.unc.edu

In the early 19th century The East India company had well established themselves and carried on their trading activities in the safety of  Ft. St. George built by them.The first lighthouse of the city, known as Madras Light, was built in 1796 on the roof of the  Exchange building where there is a Museum now. 

A simple lighthouse with a lamp was fixed  nine feet above 

Port trust 1858. Chennai Metblogs

 the sea level to help the sailors  know the shoreline as there were no tall buildings nearby;  Madras was just a small village then, so much emphasis was not given to the height of the lighthouse.

renovation.2nd lighthouse 1834,/www.deccanchronicle.com/

This lighthouse was restructured in 1820 and the height was increased to 99 feet above the sea level. An interesting feature is the lighthouse had a crude apparatus, consisting of  12 coconut oil-based lamps to produce the source light beaming through poor quality reflective mirrors that guided sailors in distress on the high seas.

 Fort St. George was built in a convenient location near the seashore at Chennapatnam (Madras) because of easy access to the incoming and outgoing ships. Outside the fort, there lay a vast land between the fort and Black town (the name does not carry a racial slur)  west of Fort St. It was more or less like an esplanade so that the British could get a good open firing range in the case of war.  

After the fire accident that destroyed a couple of Hindu temples in the 1760s in the busy area outside the fort, soon the colonial government did not wait for a long time and took over the vast land. Of course, they gave funds to have the lost temples built near the Flower Bazaar. That the fire mishap was accidental or the handiwork of the British is a moot question and it is debatable.  

By 1837, the number of ships anchoring off the First Line Beach increased and the lighthouse had to be shifted to a more convenient place. Building a much taller lighthouse gained currency among the company officials  to tackle the safe arrival of incoming ships to the harbor.  Further, in the monsoon season, the sea would become rough and this would put the cargo and passenger ships on the high seas at risk. So, based on a decision taken by the EIC officials,  a new lighthouse  came up on the land where the temples existed. The 120-feet-tall,  ornamental Doric column in the High Court complex is the city’s second lighthouse that predates the Madras High court building. In 1841, Captain J.E. Smith  designed the second lighthouse. Then the tower was tall enough to guide the ships on the  high seas. The lighthouse was successfully operated from 1838 to 1844. Since electricity was not heard of, firewood was  used widely earlier to provide light at the top of the structure to produce powerful  beam / light. 

This second Madras lighthouse in the High Court complex is not functioning and is being maintained by the  Department of Archaeology, as a protected monument. Until 1970, the lighhouse atop the ornate dome of the Madaras Hight Court served as a beacon to the sailorsA new modern lighthouse has been in service since 1970 on the marina beach.
Ref:
http://www.thehindu.com/news/cities/chennai/madras-light-comes-a-long-way/article5351916.ece