After a long time I said to myself, "Well, the son (Maharshi) seems indifferent to me. Let me go and seek refuge in my mother, Alagammal." I came and sat in the Mother’s samadhi room. It was then only a thatched room. I picked up the book Jnana Vashistha and began reading it from beginning to end with the hope of finding the solution to my dilemma. I continued reading without eating the whole day. In the evening the answer came: a stanza in Jnana Vashistha said, "Between two thoughts there is an interval of no thought. That interval is the Self, the Atman. It is pure Awareness only."
As it went on, I began to witness certain changes in my body taking place. I saw a pair of serpents rising from the base of my spine in a crisscross, spiralling manner. They rose to the crown of my head and spread their hoods. One was red; the other blue. The whole cranium became suffused with a bright light. My attention was fixed upon the point between my eyebrows where the serpents’ heads were pointed.
All of a sudden there was a splitting of the skull from the top front to the back. This was followed by an upward gush of a reddish flame shooting out from the top of my head. While this was flowing out, a stream of nectar issued from the single breast of the Ardhanareswara form of the Maharshi and a second stream of nectar flowed out from the top of Arunachala. Both streams landed on my head and sealed the break in my skull.
UPloaded word doc on Nisargadatta's tips to realization here