( 1 ) SECTION 4 of the Indian Stamp Act, 1899 as amended by the bengal Stamp (Amendment) Act, 1922, is as follows:-"4. Several instruments used in single transaction of sale, mortgage or settlement.- (1) Where, in the case of any sale, mortgage or settlement, several instruments are employed for completing the transaction, the principal instrument only shall be chargeable with the duty prescribed in schedule 1 or in Schedule 1a, as the case may be, for the conveyance, mortgage or settlement and each of the other instruments shall be chargeable with a duty of one rupee, if the principal instrument be chargeable with the duty prescribed in Schedule 1 or with a duty of (two rupees), if the principal instrument be chargeable with the duly (if any) prescribed for such other instrument in Schedule 1 or Schedule 1a, as the case may be. (2) The parties may determine for themselves which of the instruments so employed shall, for the purposes of sub-section (1), be deemed to be the principal instrument: provided that the duty chargeable on the instrument so determined shall be the highest duty which would be chargeable in respect of any of the said instruments, employed. "

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