(a)"compulsory deposit" means a subscription to, or deposit in, a Provident Fund which, under the rules of the Fund, is not, until the happening of some specified contingency, repayable on demand otherwise than for the purpose of the payment of premia in respect of a policy of life insurance, or the payment of subscriptions or premia in respect of a family pension fund, and includes any contribution and any interest or increment which has accrued under the rules of the fund on any such subscription, deposit or contribution, and also any such subscription, deposit, contribution, interest or increment remaining to the credit of the subscriber or depositor after the happening of any such contingency;
