A broker employed to sell property is not entitled to a commission where the transaction so far as it was effected by him did not amount to a sale. Viaux v. Old South Soc., 133 Mass. 1, 10; Cosgrove v. Leonard Mer., etc., Co., 175 Mo. 100, 74 S. W. 986; Johnson v. Sirret, 153 N. Y. 51, 46 N. E. 1035; Terry v. Wilson, 50 Minn. 570, 52 N. W. 973.