case Bromley versus jefferies all Freem nom Bromley v Fettiplace march Eq can  ab pl two pre Ch S c a on the marriage of his daughter to b covenant that b  shall have his land call for pound less than any other will give for it and  afterward devise this estate to his grandson for life with remainder over and  die the court refuse to decree a specific execution of this agreement by  reason of the uncertainty of it and it not be mutual sir Roland Berkley settle  his manor of Cotheridge on trustee to be by they sell after his death and the  money thereby arise to be dispose of as in the settlement be mention and as he  by his last will and testament shall appoint with a power of revocation and  afterward on the marriage of the plaintiff with one of his daughter covenant  that if the plaintiff survive sir Roland and have issue by his daughter that  the plaintiff shall have Cotheridge pound less than any other purchaser will  give for the same the plaintiff at the time of this settlement be under age  but there be also therein a covenant on his behalf that in case the plaintiff  shall purchase the say premise I e Cotheridge and have the allowance of the  say pound that then the plaintiff shall in further augmentation of the  jointure of the plaintiff Margaret his wife convey land c of pound per and to  the use of the plaintiff Margaret for her life over and above the land and  tenement agree to be settle to her use as therein mention note there be issue  of the marriage two daughter r l sir Roland live twenty year after this and by  his will revoke his settlement and devise Cotheridge and the manor of Acton  Beacham unto the plaintiff and to the defendant and Vernon chancery case other  trustee for the term of ten year upon trust to apply the profit as therein  mention remainder to his grandson green for life with remainder to his first  and other son in tail he and they take upon they the name of Berkley and  thereby inter alian give a legacy of pound r l to the plaintiff and pound to  his daughter the plaintiff wife e the court upon the hear refuse to decree a  specific execution of this agreement from the uncertainty of it because if the  estate be not to be sell but the plaintiff be to have it it be not practicable  to know what a purchaser will give for it Emery v wase Ves Blundell v  Brettargh Ves Gourlay v Somerset Ves second that the agreement be not mutual  see as to mutuality armiger v clarke bunb lawrenson v butler Sch Lef the  plaintiff be not bind to take it at any price and it be observe that as the  covenant be word if the plaintiff have die in the lifetime of sir Roland the  covenant be of no effect and it be say if sir Roland after this have a son  that shall have discharge the covenant like as in the case of Fitzherbert fol  cite in Shelleys case where the father lie sick direct his trustee to convey  to his only daughter and afterward he recover and have a son who be relievable  even by the opinion of the judge these point do not appear in the register  book by one of the answer it appear that the original settlement be find in  sir Roland study after his death cancel and that by his will he charge the  several legacy give thereby on the say estate of Cotheridge the decree as to  the execution of the covenant in specie contain mere a dismissal of the bill  but it go on to direct that if the plaintiff will accept of the say legacy of  pound with interest from sir Roland death it must be take to be in full  performance of the covenant in the say deed together with his cost Reg lib a  fol Vernon chancery case er p