resolutory condition

from Bouvier's Law Dictionary, Revised 6th Ed (1856)
RESOLUTORY CONDITION. On which has for its object, when accomplished, the 
revocation of the principal obligation; for example, I will sell you my crop 
of cotton, if my ship America does not arrive in the United States, within 
six months. My ship arrives in one month, my contract with you is revoked. 1 
Bouv. Inst. n. 764. 
    

[email protected]