In the beginning, this well understood knowledge was being passed on from generation to generation orally. The Guru (Master) will deliberate it from His memory to His sishyas (students) and the sishyas will in turn save this knowledge in their memory so that it could be passed on to their following generations.
After some time, while the significance of this knowledge was very well appreciated, the sishyas started documenting to preserve this in various forms. Primarily, they used some technique to season the palmyrah leaves to be used for the documentation of this knowledge. In this way in the Ashram (a simple place of living of a Seer, Rishi) of almost every Seer there were heaps of the bundles of palmyrah leaves containing the knowledge of all the values of life. To perpetuate this knowledge there was a continuing patronage of the kings who ruled our country Bharat (India) following the principles of governance as prescribed in those bundles to be just all the time upholding Dharma (righteousness) in their administration.
Later in the passage of time tiny segments of Bharat and their kings could not offer a powerful resistance to the invasion of the foreigners. When it was the turn of English to rule India, the English rulers being unaware of the supreme knowledge documented in those bundles simply wasted them in various ways.
Among the kings ruling different parts of India a king ruling Thanjavur (Tanjore) and its surroundings named as Sarapoji couldn’t tolerate the treasure of knowledge was slowly destroyed. Somehow or other he managed to recover the remaining bundles of knowledge, rearranged and streamlined them to be made use of. He designated this work of rearrangement, streamlining and translating in the local language such as Tamil, Telugu etc., to the pandits (scholarly persons) and preserved them to the usage of the humanity for ever.
As far as Tamilnadu (a southern part of India) is concerned in different areas different classes of people made use of this in their fields such as medicine, astronomy, black magic etc., People who used Astrology for their livelihood were under different classes such as Thenkalaisaivites, the generations of Jakkamma Naicker, Kanakkupillais and Temple Valluvas. Excepting the Temple Valluvas other classes of people gave up this profession if not they are too few to be remembered
Temple Valluvas gained the good will of the king Sarapoji, emerged as the custodians traditionally of this knowledge using and preserving the Palmyrah bundles. What is significant of this class of people is they inherit the knowledge of Astrology from their fore fathers on the one side and on the other side they gain the intellectual understanding through their personal experience by serving their Masters selflessly, and reverentially