The _Tejovindu Upanishad_ describes _Om_ as the source and focus of light in fourteen slokas, and the empyrean above it as the abode of pure ineffable light (परं ज्योतिः) of God that illumines the other spheres. (Web. p. 165). This light is viewed in the orb of the sun and in fire by their worshippers. Compare Milton’s hymn to light; “Hail holy light” &c. [Sidenote: 8. The spot of immortality अमृत बिन्दुः] Again _Om_ is termed the reservoir of immortality or endless life in the Amritavindu Upanishad which describes it in thirty stanzas, to be the eternal fountain of the infinity of lives that fills all animated nature, and is drawn back to it. Its circumference extends to the regions of light and life, and beyond it is the region of death and darkness. “In this word there is light and life” (John 1) ॐज्योतिश्च प्राणश्च । इति तत्र ६ । ४ see Weber’s A. S. Lit. pp. 69, 154, 165. [Sidenote: 9. The centre of Meditation ध्यान बिन्दुः] Therefore _Om_ is called the centre of meditation in the _Dhyánavindu Upanishad_ of twenty one stanzas, which direct the concentration of our thoughts to that centre for the attainment of perpetual light and life which flow from it. (Weber p. 165). The Tantra takes a चक्र or मुद्रा and the Buddhist a chink in the wall to fix the sight in meditation. [Sidenote: 10. The Position of Brahma ब्रह्म बिन्दुः] And lastly _Om_ is styled the receptacle of the great God, whose essence fills, pervades, and encompasses the whole orbit of the Universe, as it is described in twenty two slokas of the Brahma Vindu-Upanishad. It is called Brahma Mudrá in the Tantra. (Weber, p. p. 99, 158, 165). V. ETYMOLOGY OF THE WORD _Om_. [Sidenote: 1. Etymology of the _Om_. ॐ शब्द] Having thus far seen the mysterious nature of the letter and syllable _Om_ in its Orthography, we shall now consider it as a word, and see that not a less but much greater mystery is attached to its etymology than has been hitherto thought of by any, and which will be found upon examination to be more inscrutable in its nature than the mysteries of Eleusis and the inexplicable hieroglyphics of the Egyptian priests. [Sidenote: 2. Its symbolism of Brahmanism तद्ब्रह्मण्य ।] These secret and sacred treasures of Brahmanic enigmas and symbols, have been carefully preserved by the Brahmahood in their cabalistic writings of the Tantras, which serve to be a secure safeguard of their religion amidst the ravages of foreigners in their liberty and literature, and require to be diligently searched into for a thorough mastery of these mysticisms. [Sidenote: 3. Its derivation तदुत्पत्तिः]