The validity of a contract may be made conditional upon the existence of certain facts. If such facts do not exist the contract is of course unenforceable.1 Thus the validity of a contract may be made contingent upon the fact that the adversary party has paid a certain price for the property in question,2 that a third person buys property at a certain price,3 or that a seam of stone does not exist on a certain tract of realty.4 A contract whereby A agrees to construct a street railway as a connecting line between two roads owned by other persons, is discharged where the other roads refused to connect with such line.5 The principles of fraud, misrepresentation and mistake have no application to cases like these, where the validity of the contract is made to depend on the existence of specified facts. Hence, it makes no difference whether the fact stipulated for is an essential element of the contract or a collateral fact; or whether it is material or immaterial.6

1 Sterrioker v. McBride, 157 I11. 70; 41 N. E. 744; Miller v. Nugent, 12 Ind. App. 348; 40 N. E. 282; Dodson v. Crocker, - S. D. - ; 94 N. W. 391; Harran v. Klaus, 79 Wis. 383; 48 N. W. 479.

2 Harran v. Klaus, 79 Wis. 383; 48 N. W. 479.

3 Miller v. Nugent, 12 Ind. App. 348; 40 N. E. 282.

4Sterricker v. McBride, 157 111. 70; 41 N. E. 744.

5 Simonds v. By., 13 Conn. 513; 48 Atl. 210. Accordingly, parties who had owned such franchise, and had transferred it to A, in consideration of his agreement to build the road, cannot recover the franchise from A wheie he has surveyed the road and stopped further work, only on refusal of the other roads to make connections.

6 See Sec. 61.