Part of the lawful expense incurred in the execution of any trust is the sum paid by the trustee to a surety company for becoming surety on the bond which he is required to give by law or by order of court: Act of June 24, 1895, P. L. 248; Clark’s Est., 195 Pa. 520. The general rule is that the income, and not the principal, of a trust fund must bear the expense of administering: Spangler’s Est., 21 Pa. 335; Butterbaugh’s App., 98 Pa. 351. There is nothing in the case before us to take it out of this rule, and the decree of the Superior Court is affirmed, at appellant’s costs.