A written contract by which defendant agrees to pay plaintiff for securing a loan for him, to mortgage certain property therefor, and to "authorize, ratify and confirm every act and thing the said M. may do in negotiating said loan," covers only every act and thing touching the land to be mortgaged, and does not bind defendant to sign a mortgage containing a covenant waiving the benefit of homestead and exemption laws as to all his property. Roberts v. Matthews, 77 Ga. 458.