Where an instrument is executed to secure the payment of annuity or other sum payable periodically, or where the CC'nsideration for a conveyance is an annuity or other sum payable periodically, the amount secured by such instrument or the consideration for such conveyance, as the case may be, shall, for the purposes of this Act be deemed to be,-
(a) Where the sum ic; payable for a definite period so that the total amount to be paid can be previously ascertained-·:such total amount.
(b) Where the sum is payable in perpetuity or for an indefi nite time not terminable with any life in being at the date of such instrument or conveyance-the total amount which accord.
ing to the terms of such instrument or conveyance will or may be payable during the period of twenty years calculated from the date on which the first payment becomes due; and
(c) Where the sum is payable for an indefinite time termi nable with any life in being at the date of c;uch instrument or conveyance-the maximum amount which will or may be payable as aforesaid during the period of twelve years calculated from the date on which the first payment becomes due.
27. Stamp wlzere 'D'llue of subject matter ts it~dclerm•11ale-Where the amount or value of the subJect matter of any instrument charge able with advalorem duty cannot be or could not hava been, as certained at the date of its execution, or first execution, nothing shall be claimable under such instrument more than the highest amount or value for which, if stated in an instrument of the same description, the stamp actually used would; at the date of such execution have been sufficient:
Provided that, in the case of the lease of mine in which roy alty or a share of the produce is received as the rent or the part of the rent it shall be sufficient to have estimated such royalty or the value of such share, for the purpose of stamp du!Y-
(a) When the lease has been granted by or on behalf of the Government, at such amount or value as the Collector may hav ing regard to all the circumstances of the case, have estimated as likely to be payable by way of royal!ty or share to the Govern ment under the lease, or 13(}
(b) whetl the lease has been granted by any other person, at twenty thousand rupees a year;
and the whole amount of such royalty or share, whatever it ....e may be, shall be claimable under such lease:
Provided also that, where proceedings have been taken in respect of any iustrJment under section 31 or 39 the amount certified by the Collector shall be deemed to be tht> stamp actually used at the date of execution