Verse 17

शतत्रये स वर्षाणामथ याते स्वयंप्रभुः ।व्यबुध्यतात्मरूपात्मा धराकोटरपीडितः

In plain words

Then, when three hundred years had passed, that self-sovereign one, whose very self is the form of ātman, awoke, pressed hard by the earth's hollow.