s 23 Aggregation of property to form one estate for purpose of estate duty
23.—(1) For determining the rate of duty to be paid on any property passing on the death of the deceased, all property so passing in respect of which duty is leviable shall be aggregated so as to form one estate, and the duty shall be levied at the proper graduated rate on the principal value thereof. (2) Any property so passing, in which the deceased never had an interest, shall not be aggregated with any other property, but shall be an estate by itself, and the estate duty shall be levied at the proper graduated rate on the principal value thereof. (3) Property passing on any death shall not be aggregated more than once, nor shall estate duty in respect thereof be more than once levied in respect of the same death.