Section 16: In the case of debentures redeemable on a fixed date, the

Crown Agents shall place at interest or invest in the purchase of such securities as may be approved by the Secretary of State so much of the money so remitted to them as aforesaid as shall not be required for the payment of interest for the current half-year, as a sinking fund for the final extinction of the debt, and the Crown Agents shall also place at interest or invest in the purchase of like securities the accumulations of interest or the dividends, interest or produce of such investments and may, from time to time, with the approval of the Secretary of State, change any such investments and shall hold such fund in trust for the repayment of the principal moneys for the time being represented by the debentures.