It is manifest that the foregoing agreement imposes no obligation whatever on Helber to purchase from the plaintiffs any definite quantity of gasoline or indeed any gasoline at all. It only required him to use the equipment furnished by the plaintiffs in the handling and sale of any gasoline purchased from them and prohibited Helber from using said equipment in the sale of any gasoline not purchased from the plaintiffs or for any other purpose. The record discloses that there was no oral evidence offered in the trial of the case that in any way reflected on any understanding between the parties as to their liability except as was expressed in the written contract. There is no evidence in the trial of any additional obligations assumed by either party. At the close of plaintiffs’ evidence the trial court directed the jury to return a verdict in favor of the defendants, which this court concludes was the only course open for the trial court and the judgment of that court is therefore affirmed.