A broker may recover a commission of his principal, although the sale made is not consummated, if it fails solely on account of a defect in the vendor's title of which the broker was neither notified nor had personal knowledge, although the commission was to be paid out of the proceeds of sale. Cheatham v. Yar-brough, 90 Tenn. 77, 15 S. W. 1076. See also Sec. 570. For the contrary doctrine, where actual sale was not made as provided by contract. Bull v. Price, 7 Bing. (Eng.) 237, 9 L. J. C, P., O. S. 78. See also Sec. 458.