A writing in express terms empowering and authorizing real •estate brokers to sell land for $1,000, or as much less as the owner might take, binding the brokers to accept as remuneration any sum they might obtain in excess of the sum stipulated that the owner should receive, was a contract of agency and not an option to the brokers to purchase the land. Tate v. Aitken, 5 Cal. App. 505, 90 P. 836. See also Sec. 82.