“ Considering the plain provision in § 64a of the bankruptcy act, that 'the court shall order the trustee to pay all taxes legally due and owing by the bankrupt . . . in advance of the payment of dividends to creditors' [30 Stat. at L. 563, chap. 541, Comp. Stat. 1913, § 9648] , we entertain no doubt of the propriety of requiring that the certificate holders, who had paid the taxes and assessments at the sales, be reimbursed upon the cancelation of their certificates, or of requiring that the reimbursement be out of the general assets. ”

“ They were not in a position to stand upon the terms of the redemption statute, for the sales were invalid, and the only recognition which they could ask was such as resulted from an application of equitable principles to their situation. The decree of the Circuit Court of Appeals is modified to conform to what is here said respecting the allowance of interest. In other respects it is affirmed. ”