The Theosophical (along the teachings of Alice Bailey) theoreticician and Radionics practitioner writer David Tansley has this to say about chakras in his book Radionics and the Subtle Anatomy of Man

"A chakra may be defined as a focal point for the  reception and transmission of energies.  These energies can originate from a variety of sources, some cosmic, others from the collective unconscious of a nation or humanity..., or from the physical, emotional and mental worlds of the lower self...
The chakras have three main functions:

1. To vitalize the physical body
2. To bring about the development of self-consciousness
3. To transmit spiritual energy in order to bring the individual into a state of spiritual being.

  These centres are in the nature of dis-tributing energies, providing dynamic force and qualitative energy....They produce definite effects upon (one's) outward physical appearance, and through their continuous activity...character tendencies emerge." [Radionics & the Subtle Anatomy of  Man", pp23-4]

Tansley explains the origin of the chakras as  resulting from the intercrossing of etheric force  lines:

The chakras in the etheric body come into being where the strands of energy cross and re-cross each other.  The seven major chakras form where these lines cross...twenty-one times.  The minor chakras, of which there are twenty-one (fig  ), occur where the energy strands cross fourteen times.  Where the lines cross seven times, lesser focal points are  created....Beyond this are many tiny force centres, which probably correspond to the acupuncture points of Chinese medicine." [pp 23-4]

These actual numbers are arbitrary - like most Theosophical esotericists, Tansley is obsessed with the number seven, and has to explain everything in terms of sevens and multiples of sevens.