Webover 300 hours of secret tapes recorded at the white house during the spring and summer of 1973 cover a tumultuous period, when revelations about the. 4,000 hours of still secret tape recordings from the darkest days of. Webin july of 1973, the senate watergate committee cornered richard nixon. His oval office had a secret recording system. The tapes suggested a criminal conspiracy. Webwhite house lawyers disclose to sirica that one of the tapes has a gap of more than 18 minutes in the middle of a long conversation between nixon and.