"Where a principal's name is signed by the agent at the request of the principal, and in his presence, the signature is deemed that of the principal himself, since the agent does not act in that capacity, but merely as the hand or amanuensis of the principal, and in such case the agent signs the principal's name only as if the principal had himself signed it. Gardner v. Gardner, 5 Cush. (Mass.) 483; B. I. & St. L. B. Co. v. Shunick, 65 I11. 223; Meyer v. King, 29 La. Ann. 567, 569. Compare Sec. 18.