Section 72(2)(a) in The Calcutta Improvement Act, 1911
(a)[ a person who was or has been a member of the Judicial Service as defined in Article 236 of the Constitution of India for at least ten years and held a rank not inferior to that of a Subordinate Judge for at least three years; or] [Clauses (a) and (b) substituted by W. B. Act 32 of 1955.],