Hereafter all bequests and devises in trust for the purpose of applying the entire interest or income thereof to the care and preservation of the family burial lot or lots of the donor, in good order and repair perpetually, shall be exempt from liability for collateral inheritance tax. This act shall take effect on and after the first day of January, 1904, and shall not apply to any bequest or devise, as aforesaid, made prior to that time.
9 P.S. § 6