280, 52 N. E. 432, 42 L. R. A 797, 69 Am. St. Rep. 242; Warner v. Bennett, $1 Conn. 475; Blean v. Messenger, 33 N. J. Law, 503. A condition subsequent is one annexed to an estate already vested, by the per formance of which such estate is kept and continued, and by the failure or non-performance of which it is: defeated; or it is a condition referring to a future event, upon the happening of which the obligation becomes no longer binding upon the other party, if he chooses to avail himself of the condition. Co. Litt. 201; 2 BL:C al. 1436;