... it is there as a very subtle centre on the right side of the chest
चित्तमणीयो वित्तं य इदं मूल्ये प्रपञ्चतोऽप्यधिकम् ।
हृदयगुहायां निहितं जानीते स विजहाति बहिराशाः ॥ ४.२१॥
cittamaṇīyo vittaṁ ya idaṁ mūlye prapañcato'pyadhikam |
hṛdayaguhāyāṁ nihitaṁ jānīte sa vijahāti bahirāśāḥ ॥ 4.21॥
“Whoever has found the pure mind, encamped within the Cave of the Heart, worth more than the conceptual universe, gives up all desires.” (trans. MWright)
Here is Ramana’s explanation of the above verse from Umasahasram as found in Nayana’s Biography by Dr G. Krishna (1978; p. 194):
“Ramana explained slowly - Nayana has extolled the very precious nature of Chitta in the first sloka and then explained his own experience gained by spiritual practice. Though the radiance passing from Heart to head gets entangled in external influences due to its association with sense organs, it will be experienced in its pristine purity by those who arrest the flow of the current in between in the Amritanadi. This radiance is not anything different form the Pure Awareness of the Heart. Chitta is the subtlest essence of the mind and intellect. What proceeds to the Head from the Heart is that pure radiance. Chitta Aakaasa and Chidaakaasa coalesce inseparably. The heart is the support of the Universe as well as the body. The universe and the body are inhering in this subtle all pervading Heart. Whence all knowledge and activity arise in the Jiva it is called the Heart. It has to be understood by experience; it is there as a very subtle centre on the right side of the chest.”