When property is purchased by the husband, and at the same time mortgaged by him to secure payment of the purchase money, such mortgage may be executed by the husband alone, and does not require the signature of his wife to make it valid. And sections 797 and 798 of the R. S. D. C., act of Congress of February 5, 1867, do not exempt property so purchased from the operation of the lien created by such mortgage to secure the purchase money, notwithstanding that such property may not exceed in value the amount exempted under said act from execution, &c.

The deed of trust from Twombly to Randall, trustee, is valid ; and the decree below is affirmed.