Vibrations are the feeling of the all pervading Divine Power within yourself on your central nervous system. You can feel the Divine Power for the first time after Self Realization on your central nervous system ending up into your finger tips where the sympathetic centers are located. So you start feeling on your hand the universal language which is spoken by the hand, the different centers and thus you know a rapport is established between the spirit and yourself. Because when you ask a question about any fundamental problem, you either get a cool breeze blowing into your hands or you just stop it. Sometimes you might get some blisters also if the person is suffering from some sort of very great maladjust. You might get numbness if the person is on his way to death or could be very freezingly cold. So the hands start "speaking" as said by Mohammad Sahib that "Your hands will speak when the time of resurrection will come". This is the time of resurrection because kundalini resides in the sacrum which is the Aquarius. This is the age of the Aquarius. This is the age of the kundalini.
Shri Mataji Nirmala Devi February 10, 1982 ( 1983 ? ) "Questions and Answers About America" New Delhi, India
(From the DCB Publication : One Hundred Questions - Answers to Calm Our Greatest Concerns)