say, upon trust, that they my said trustees and the survivor of them, and the executors and administrators of such survivor, do and shall lay out and invest the same in the public stocks or funds, or upon government or real security at interest, with power from time to time to change, vary, and transpose such securities, and from time to time during the life of my sister Augusta Mary Leigh, the wife of George Leigh, Esquire, pay, receive, apply, and dispose of the interest, dividends, and annual produce thereof, when and as the same shall become due and payable, into the proper hands of the said Augusta Mary Leigh, to and for her sole and separate use and benefit, free from the control, debts, or engagements of her present or any future husband, or unto such person or persons as she my said sister shall from time to time, by any writing under her hand, notwithstanding her present or any future coverture, and whether covert or sole, direct or appoint; and from and immediately after the decease of my said sister, then upon trust, that they my said trustees and the survivor of them, his executors or administrators, do and shall assign and transfer all my said personal estate and other the trust property hereinbefore mentioned, or the stocks, funds, or securities wherein or upon which the same shall or may be placed out or invested, unto and among all and every the child and children of my said sister, if more than one, in such parts, shares, and proportions, and to become a vested interest, and to be paid and transferred at such time and times, and in such manner, and with, under, and subject to such provisions, conditions, and restrictions, as my said sister, at any time during her life, whether covert or sole, by any deed or deeds, instrument or instruments, in writing, with or without power of revocation, to be sealed and delivered in the presence of two or more credible witnesses, or by her last will and testament in writing, or any writing of appointment in the nature of a will, shall direct or appoint; and in default of any such appointment, or in case of the death of my said sister in my lifetime, then upon trust that they my said trustees and the survivor of them, his executors, administrators, and assigns, do and shall assign and transfer all the trust, property, and funds unto and among the children of my said sister, if more than one, equally to be divided between them, share and share alike, and if only one such child, then to such only child the share and shares of such of them as shall be a son or sons, to be paid and transferred unto him and them when and as he or they shall respectively attain his or their age or ages of twenty-one years; and the share and shares of such of them as shall be a daughter or daughters, to be paid and transferred unto her or them when and as she or they shall respectively attain her or their age or ages of twenty-one years, or be married, which shall first happen; and in case any of such children shall happen to die, being a son or sons, before he