Time and manner of conversion and investment. Interest payable until investment.

Such conversion and investment as are contemplated by the last preceding section shall be made at such times and in such manner as the executor in his discretion thinks fit ; and, until such conversion and investment shall be completed, the person who would be for the time being entitled to the income of the fund when so invested shall receive interest at the rate of six per cent per annum upon the market-value (to be computed as of the date of the testator’s death) of such part of the fund as shall not yet have been so invested.