"Where a broker was employed to sell a whole tract of land, or a part thereof, and after negotiating the broker failed to make a sale and an attempt was made to discharge him; but he continued his negotiations, and subsequently the owner sold a portion of the tract to a person with whom the broker had prior negotiations, the owner was held liable to pay the broker a proportionate commission. Diamond v. Wheeler, 80 N. Y. S. 416, 80 App. Div. 58; Thompson v. Sargeant, 134 P. 7, 66 Or. 384; B. J. & B. F. Camp Lumber Go. v. Teddie, 82 S. 86, - Fla. Sup. See to contrary, Carpenter v. Atlas Imp. Co., 108 N. Y. S. 547, 123 App. Div. 706. See also Secs. 455, 967.