Registration Act, 1908–Secs. 17 & 49–Scope–Unregistred documents required to be registered are inadmissible in evidence for the purpose of conveying title or completing a sale transaction, and can only be admitted for collateral purposes or in a suit for specific performance–Instant suit was for declaration, permanent injunction and possession–Power of attorney ex-ecuted in favour of the respondent was unregistered and had already been revolved prior to execution of sale deeds–He could not had relief on the unregistered documents to assert any proprietory rights and had no valid authority to execute the impugned sale deeds.